TECHNICAL FIELD
[0001] The present invention relates generally to the fields of test devices that include
a sample receiving chamber and a test platform and methods of use thereof. Preferably,
the sample receiving chamber can be used to extract, prepare or dilute a sample for
analysis, such as using the test platform. The test platform can include a test element,
such as a test strip. The test strip can be for an analyte of interest, such as an
analyte relating to a disease state, medical condition or etiological agent.
BACKGROUND
[0002] A variety of sample collection and extraction test devices for clinical or home use
are available and described in the literature. These test devices can utilize one
of a variety of collection instruments to obtain and transfer a sample to a receptacle.
The sample can be extracted from the collection device and diluted or mixed with one
or more reagents in the receptacle. The sample can then be conveyed to a test element
in order to determine the presence or absence of a substance, such as analyte detection.
These devices can be used for an assortment of purposes, including the detection of
drugs or biological compounds such as glucose or hormones, antibodies or etiological
agents. Many of these devices are inefficient in sample extraction from the collection
device. Also, many of these devices are complex in design and manufacture and fabricated
of relatively expensive materials. The present invention addresses these problems,
and provides related benefits.
[0003] US 5,658,531 discloses a disposable assay device for assaying a sample comprising a body having
a reaction chamber for receiving an assay reagent sensitive to a component being assayed
for in the sample, said reaction chamber being closed by a slidable valve plate carried
on a support and cooperating with an annular seat around a sample entrance hole, wherein
the valve plate is provided with a passage therethrough being closed by the support,
and moveable by means of a compressed foam pad which expands when wetted; a sample
collector/dispenser having means for collecting the sample to be assayed and a means
for dispensing a predetermined quantity of the sample collected through the sample
entrance hole; means for non-detachably engaging said body with said collector/dispenser;
and a means for sealing said body with said collector/dispenser when non-detachably
engaged to prevent leakage of a collected sample, reagent and mixtures thereof from
said reaction chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004]
FIG. 1 depicts one aspect of a test device of the present invention in use. The sample receiving
chamber 1 is engaged to the test platform 2 that houses a test element, in this case an immunochromatographic test strip 3. A swab 4, with the sample on the swab head 5, is inserted through an opening in the top or proximal end 6 the sample receiving chamber 1. A reagent 7 containing components for an appropriate test is deposited through the proximal opening
6 into the sample receiving chamber 1 where the sample is extracted into the reagent. The fluid mixture comes into fluid
contact with a sample application area of the test strip 3 and wicked by capillary flow 8 along the test strip 3. The presence of a visible line at a detection zone 9 of the test strip 3, observed through an opening 10 of the test platform 2, indicates the presence of an analyte in the sample. The presence of a line at a control
region 11 of the test strip 3 indicates a successful assay.
FIG. 2A depicts one aspect of a test device of the present invention, wherein the sample
receiving chamber 1 is separate from the test platform 2 housing an immunochromatographic test strip 3. A valve structure 20 is located at the distal end of the disengaged sample receiving chamber 1 such that
when in the closed position no fluid can flow out of the bottom or distal end 21 of the sample receiving chamber 1. A reagent 7 containing components for an appropriate test is deposited via the proximal opening
6 into the sample receiving chamber 1 and a swab 4, with the sample on the swab head 5, is inserted through the opening at the top or proximal end 6 the sample receiving chamber 1. The distal end 21 of the sample receiving chamber 1 engages the test platform 2 at the aperture 22 such that it is substantially perpendicular to the test platform 2. After incubation of the sample in reagent the valve 20 is rotated such that the valve is opened and the fluid contents are released at a
controlled flow onto a sample application area of the test strip 3. The fluid is wicked by capillary flow 8 along the test strip 3 and the presence of a visible line at a detection zone 9 of the test strip 3, observed through an opening 10 of the test platform 2, indicates the presence of a specific analyte in the sample. The presence of a line
at a control region 11 of the test strip 3 indicates a successful assay.
FIG. 2B depicts a test platform 2 with an aperture 23 the shape of which, in this instance, is partially circular on one side with a triangular
edge on the other side of the aperture such that the aperture 23 can only accept and support a sample receiving chamber with a specific key structure
at its distal end.
FIG. 3 depicts the test strip, a single strip or a strip comprised of multiple regions in
fluid communication, that can be housed within the test platform. FIG. 3A depicts a cross section view along axis A-A of a test platform 2 of the present invention housing a test element, in this instance a single strip
immunochromatographic test strip 3. The cross-section of an aperture 22 and opening 10, through which the detection and control zones of the immunochromatographic test strip
3 can be observed, are depicted. FIG. 3B depicts a test strip 3 comprised of multiple regions, in this instance having overlapping regions in order
to be in fluid communication when a fluid is traveling via capillary flow. The test
strip is made up of an application zone 30 in fluid communication with an optional second strip 31 with reagent zone 32. The second region 31 is in turn optionally in communication with a third region 33 with a sample detection zone 9 and optional control zone 11, overlapped by a fourth region 34 that promotes wicking of fluid through the test strip. FIG. 3C depicts a test strip 3 comprised of multiple regions, in this instance having regions end-to-end or overlapping
in order to be in fluid communication when a fluid is traveling via capillary flow
along the test strip. The test strip is made up of an application zone 30 with a downstream region optionally having label 32. A second strip 33 with a detection zone 9 and optional control zone 11 is adjacent to, and in fluid communication with the first region 30. And a third region 34 that promotes wicking of fluid through the test strip overlaps the second region
33.
FIG. 4 depicts several mechanical structures that can be located, as viewed, at or near
the distal end of a sample receiving chamber. In the closed position the contents
are retained in a sample receiving chamber. In the opened or partially opened position
the contents are released in a regulated flow of a sample, or a sample and reagent,
from a sample receiving chamber of the present invention. For example, FIG. 4A depicts a twist valve 40 such that openings of the valve do not aligned 41 and the valve is closed. Optionally the valve can be rotated such that openings align
42 and the valve is in the open position. Any intermediate alignment between the openings
can be used as a way to regulate flow. FIG. 4B depicts a thin membrane and puncturing mechanism where a puncturable membrane 43 retains contents at the distal end of a sample receiving chamber and optionally a
puncturing device 44 can come into contact with the puncturable membrane to rupture the membrane 45. However, Fig. 4B does not form part of the invention. FIG. 4C depicts a slide valve where an opening at the distal end of the sample receiving
chamber is covered by a slide 46 to close the outlet 47 and when slid into a second position the opening is uncovered and provides an outlet
48 for the contents. FIG. 4D depicts a stopcock mechanism where the stopcock 49 can be rotated such that an outlet 50 is provided for the contents of the sample receiving chamber.
FIG. 5 depicts a sample receiving chamber 1 of the present invention showing internal longitudinal ribs 51 that alternately constrict the interior of the chamber.
FIG. 6 depicts one aspect of a sample receiving chamber 1 of the present invention. FIG. 6A depicts a front view, and FIG. 6B depicts a side view, of a male insert 60 of the sample receiving chamber 1. A grooved ridge 61 encircles the opening or proximal end 6 of the male insert 60. A stud 63 protrudes from, and an opening or outlet port 64 are positioned on the side wall of a cylindrical shaft 62 of the male insert 60. The outlet port 64 is flanked, above and below, by O-rings 65 that encircle the cylindrical shaft 62 of the male insert 60. FIG. 6C depicts a front view, and FIG. 6D depicts a side view, of a female receptor 66 of the sample receiving chamber 1. The female receptor 66 has a base 67 with a notch 68 for proper placement onto a test device of the present invention. An open groove
guide 69 is situated along the side of the female receptor 66. FIG 6E depicts the sample receiving chamber 1 in the closed position. The male insert 60 is coupled to the female receptor 66 such that the stud 63 sits near the top of the of the groove guide 69 and the outlet port 64 faces the inner wall of the female receptor 66 such that fluid cannot exit the sample receiving chamber 1. FIG. 6F depicts a sample receiving chamber 1 in the open position where upon rotation of the male insert 60, the groove guide 69 conveys the stud 63, and therefore the male insert 60, downward such that the outlet port 64 is below the inner wall of the female receptor 66.
FIG. 7 depicts several designs for keys that can be used in the present invention, preferably
for engaging or orienting the sample receiving chamber 1 with a test platform 2. For example, FIG. 7A depicts a key 71 of a sample receiving chamber 1 that has a single orientation whereas FIG. 7B depicts a key 71 with a wide variety of orientations, essentially infinite due to the circular structure
of the key 71. FIG. 7C depicts a key 71 with a sample receiving chamber 1 that can have between one and five orientations, whereas the key 71 and sample receiving chamber 1 of FIG. 7D can have between one and four orientations, the key 71 of a sample receiving chamber 1 in FIG. 7E can have between one and seven orientations, and the key 71 and sample receiving chamber 1 of FIG. 7F can have between one and three orientations. As set forth in FIG. 7D the key 71 can include a plurality of sample receiving chambers 1 which can include a sample or can be left unloaded with sample. As set forth in FIG. 7F, the key 71 can be color coded, for example blue (left side) and red (right side) of the upper
figure. Such color coding can match color coding or other coding presented on a second
device such that the sample receiving chamber 1 is properly aligned with the second device. Such orientation coding can also be accomplished
as set forth in FIG. 7G, where the key 71 has structure such that it can engage a test platform in one orientation such that
the sample receiving chamber 1 is aligned with a predetermined location. This aspect of the present invention is
preferable when more than one sample receiving chamber 1 of the present invention is used to engage a test platform, such as a device that
can collect or analyze a plurality of analytes. For example, a test platform 2 can house more than one test element, each specific for different analytes, such
as two different test strips 3. The chemistry on the two different test strips can be different such that different
reagents in the sample receiving chamber are desirable. In this way, using color coding
alone, orientational coding or a combination thereof, the operator can engage the
sample receiving 1 chamber with a test platform 2 such that sample dispensing at a defined or predetermined locus is accomplished.
The outlet or outlets 72 for each key is illustrated.
FIG. 8A depicts a top view of an engaging structure 80 on a test platform 2 that can engage a key 71, such as set forth in FIG. 7A. The engaging structure can lock such as by reversibly engaging or irreversibly engaging
the key 71 and thus the sample receiving chamber 1. The dashed lines indicate a channel under the surface of the structure that can accept
the rotation of the key 71 in FIG. 7A.
FIG. 8B is a cross section view along axis A-A showing the engaging structure 80 and the test platform 2 that includes a test strip 3 that can include a sample application zone 30 and optionally sample detection zone or sample detection zones 9 and optionally control zone or control zones 11 as those terms are known in the art, and as are set forth in commonly assigned United
States Patent Application No. 09/579,673 filed May 26, 2000, (US-A-579673).
FIG. 9A through FIG. 9F depict a test platform 2 that include one or more engaging structures 80 that can engage one or more keys 71 of sample receiving chamber of the present invention. The test platform 2 in this instance is a multi-channel test device that includes a plurality of test
strips 90 for a variety of analytes, such as Strep (Streptococcus), hCG (human chorionicgonadotropin), COC (cocaine) and HIV (human immunodeficiency
virus) as depicted by surface indicia 91, thus including tests for etiological agents, pregnancy and drugs of abuse. As shown
in FIG. 9B through FIG. 9F, a variety of keys 71 can be used to encode a sample collection and dispensing device of the present invention
for use to engage an appropriate engaging structure 80. The reagent in a sample receiving chamber 1 can be tailored to the test being performed
on the test element, which can be coded by the key 71 and the engaging structure 80.
SUMMARY
[0005] The present invention recognizes that it can be desirable to have a sample receiving
chamber engageable with a test platform; such as a test platform that includes a test
strip. The sample receiving chamber is separate or separable from the test platform.
A fluid flow actuating or modulating device or structure, such as a valve separates
the sample receiving chamber from the test platform. The present invention provides
such a device and methods of use.
[0006] The present invention provides a test device having the features of claim 1.
[0007] Further, the present invention provides a method of detecting an analyte in a sample
having the features of claim 27.
[0008] Further embodiments of the invention are described in the dependent claims.
DETAILED DESCRIPTION OF THE INVENTION
DEFINITIONS
[0009] Unless defined otherwise, all technical and scientific terms used herein have the
same meaning as commonly understood by one of ordinary skill in the art to which this
invention belongs. Generally, the nomenclature used herein and the manufacture or
laboratory procedures described below are well known and commonly employed in the
art.
Conventional methods are used for these procedures, such as those provided in the
art and various general references. Terms of orientation such as "up"and "down" or
"upper" or "lower" and the like refer to orientation of the parts during use of the
device. Where a term is provided in the singular, the inventors also contemplate the
plural of that term. The nomenclature used herein and the laboratory procedures described
below are those well known and commonly employed in the art. As employed throughout
the disclosure, the following terms, unless otherwise indicated, shall be understood
to have the following meanings:
An element of the present invention is "integral to" another element of the present
invention when the two elements are manufactured as a single piece.
An element of the present invention is "separate from" another element of the present
invention when the two elements are manufactured as separate pieces.
"Proximal" refers to the upper end of a sample receiving chamber and provides an orifice
for insertion of materials such as sample, sample collection device, and reagents
into the sample receiving chamber.
"Distal" refers to the end of a sample receiving chamber that is opposite to and farthest
from the proximal end of the sample receiving chamber and is that end that provides
an outlet from the sample receiving chamber.
"Directly" means that one structure is in physical contact with another structure,
or, when used in reference to a procedure, means that one process effects another
process or structure without the involvement of an intermediate step or component.
"Indirectly" means that one structure is not in immediate physical contact with another
structure, but rather contacts an intermediary structure that contacts the other structure.
When used in reference to a procedure, "indirectly" means that one process effects
another process or structure by means of an intermediate step or component.
A "reagent" can be any chemical, including organic compounds and inorganic compounds
and combinations thereof. A reagent can be provided in gaseous, solid, or liquid form,
or any combination thereof, and can be a component of a solution or a suspension.
A reagent preferably includes fluids, such as buffers useful in methods of detecting
analytes in a sample, such as anticoagulants, diluents, buffers, test reagents, specific
binding members, detectable labels, enzymes and the like. A reagent can also include
an extractant, such as a buffer or chemical, to extract an analyte from a sample or
a sample collection device. For example, a buffer can be used to free biological components
such as cells or etiological agents on or within a sample collection device, such
as a swab. Alternatively, an extractant, such as an acid, can be use to extract analytes
from the sample, such as LPS from bacteria.
A "barrier" is a thin piece of material that is not rigid. By "thin" it is meant that
the thickness of the material is lesser that either its length or width. A "puncturable
barrier" of the present invention can be punctured by a puncturing structure when
brought into contact with a puncturable barrier with sufficient force. A puncturing
structure can protrude through a puncturable barrier. Suitable materials for barriers
include foils, plastics, and foil-plastic laminates.
A "key for engaging a test platform" or "key" of a sample receiving chamber of the
present invention is a structure that can engage a second device, such as a test platform.
A key can be integral to a sample receiving chamber of the present invention, or can
be separate from a sample receiving chamber of the present invention and can engage
a sample receiving chamber. Use of a key to engage a sample receiving chamber with
a test platform can position a sample receiving chamber of the present invention such
that sample can be dispensed into the appropriate area of a second device.
A "test element" is an element for analyzing a sample. A test element can be used
to detect the presence and/or concentration of an analyte in a sample, or to determine
the presence and/or numbers of one or more components of a sample, or to make a qualitative
assessment of a sample. Test elements of the present invention include, but are not
limited to, cuvettes, slides, lateral flow detection devices such as test strip devices,
and columns.
A "lateral flow detection device" is a device that determines the presence and/or
amount of an analyte in a liquid sample as the liquid sample moves through a matrix
or material by lateral flow, such as an immunochromatographic device.
"Sample application aperture" refers to the portion of a test platform where an opening
provides access to the portion of the test platform that receives the sample. For
example, a sample application aperture can provide access to a sample application
zone of a test strip, or a plurality of test strips, of a lateral flow detection device.
"Analyte" is the compound or composition to be measured that is capable of binding
specifically to a ligand, receptor, or enzyme, usually an antibody or antigen such
as a protein or drug, or a metabolite. The precise nature of antigenic and drug analytes
together with numerous examples thereof are disclosed in U.S. Pat. No. 4,299,916 to Litman, et al., particularly columns 16 to 23, and in U.S. Pat. No. 4,275,149, columns 17 and 18. Analytes can include antibodies and receptors, including active
fragments or fragments thereof. An analyte can include an analyte analogue, which
is a derivative of an analyte, such as, for example, an analyte altered by chemical
or biological methods, such as by the action of reactive chemicals, such as adulterants
or enzymatic activity.
"Antibody" is an immunoglobulin, or derivative or fragment or active fragment thereof,
having an area on the surface or in a cavity which specifically binds to and is thereby
defined as complementary with a particular spatial and polar organization of another
molecule. The antibody can be monoclonal or polyclonal and can be prepared by techniques
that are well known in the art such as, for example, immunization of a host and collection
of sera or hybrid cell line technology.
"Control analyte" is a compound present in the sample or reagent chamber that can
be detected by an analysis device. Detection of the control analyte in the control
zone indicates that fluid has moved throughout the analysis device.
"Sample" is any material to be tested for the presence and/or concentration of an
analyte in a sample, or to determine the presence and/or numbers of one or more components
of a sample, or to make a qualitative assessment of a sample. Examples of liquid samples
that may be tested using a test device of the present invention include bodily fluids
including blood, serum, plasma, saliva, urine, ocular fluid, semen, and spinal fluid;
water samples, such as samples of water from oceans, seas, lakes, rivers, and the
like, or samples from home, municipal, or industrial water sources, runoff water or
sewage samples; and food samples, such as milk or wine. Viscous liquid, semi-solid,
or solid specimens may be used to create liquid solutions, eluates, suspensions, or
extracts that can be samples. For example, throat or genital swabs may be suspended
in a liquid solution to make a sample. Samples can include a combination of liquids,
solids, gasses, or any combination thereof, as, for example a suspension of cells
in a buffer or solution. Samples can comprise biological materials, such as cells,
microbes, organelles, and biochemical complexes. Liquid samples can be made from solid,
semisolid or highly viscous materials, such as soils, fecal matter, tissues, organs,
biological fluids or other samples that are not fluid in nature. For example, these
solid or semi-solid samples can be mixed with an appropriate solution, such as a buffer,
diluent, extraction buffer, or reagent. The sample can be macerated, frozen and thawed,
or otherwise extracted to form a fluid sample. Residual particulates can be removed
or reduced using conventional methods, such as filtration or centrifugation.
[0010] Other technical terms used herein have their ordinary meaning in the art that they
are used, as exemplified by a variety of technical dictionaries.
INTRODUCTION
[0011] The present invention recognizes that it can be desirable to have a sample receiving
chamber engageable with a test platform, such as a test platform that includes a test
strip. The sample receiving chamber is separate or separable from the test platform.
A fluid flow actuating or modulating device or structure such as a valve separates
the sample receiving chamber from the test platform. The valve structure is positioned
at the distal or outlet end of the sample receiving chamber whereupon when engaged,
the valve structure can actuate or modulate flow from the sample receiving chamber
into the test platform. The present invention provides such a device and methods of
use.
[0012] As a non-limiting introduction to the breath of the present invention, the present
invention includes several general and useful aspects, including:
- 1) a test device that includes a sample receiving chamber and a test platform that
includes a test element, where the sample chamber engages the test platform and is
separable therefrom; and
- 2) a method of detecting an analyte in a sample, including providing a sample, contacting
the sample with a test device of the present invention and detecting the analyte in
the sample, if present.
[0013] These aspects of the invention, as well as others described herein, can be achieved
by using the methods, articles of manufacture and compositions of matter described
herein. To gain a full appreciation of the scope of the present invention, it will
be further recognized that various aspects of the present invention can be combined
to make desirable embodiments of the invention.
I TEST DEVICE
[0014] The present invention includes a test device that includes a sample receiving chamber
1 and a test platform
2 that includes a test element. The sample receiving chamber
1 engages the test platform
2 and is separable therefrom as depicted in
FIG. 1 and
FIG. 2. When engaged the sample collection chamber
1 and test platform
2 are preferably substantially perpendicular. The sample receiving chamber
1 can accept a sample directly or by way of a sample collection device such as, but
not limited to, a rod, spoon, spatula, knife, brush, or fabric, but is preferably
a swab
4. Optionally the sample receiving chamber
1 can contain one or more reagents prior to transfer of the sample. In another aspect
of the present invention one or more reagents
7 can be added to the sample receiving chamber before transfer, during transfer or
post transfer, of the sample into the sample receiving chamber
1. The sample can incubate with the reagent or reagents
7 for an approximate or specific period of time prior to transfer into the sample receiving
chamber
1 or can incubate within the sample receiving chamber
1. The contents of the sample receiving chamber
1, when engaged with the test platform
2, can be released into the test platform
2 by way of structures such as the opening of a valve. Upon release from the sample
receiving chamber
1 the sample, with or without one or more reagents, can come into fluid contact with
the test platform
2 and thereby a test element associated with the test platform such as, but not limited
to, an immunchromatographic test strip
3.
SAMPLE RECEIVING CHAMBER
[0015] The sample receiving chamber
1 includes a proximal end
6 and a distal end
21, wherein the proximal end
6 can receive a sample and the distal end
21 can directly or indirectly engage a test platform
2 of the present invention. In one aspect the contents of a sample receiving chamber
1 can be released through the distal end of the sample receiving chamber
1, preferably into a test platform
2 as depicted in
FIG. 1. The sample receiving chamber
1 can be of any geometric shape or dimension such as, but not limited to, triangular,
spherical, oval, square, rectangular, pentagonal, hexagonal, heptagonal, octagonal,
or any polygon, or non-geometric shape such as kidney or bean shaped, but is preferably
substantially cylindrical. The size of the sample receiving chamber
1, encompassing such dimensions as the width, height and diameter of the sample receiving
chamber
1 can be such that an indiscriminate or predetermined volume of a sample can be efficiently
transferred to the sample receiving chamber
1, or can readily accept insertion of a sample and sample collection device
5 and if desirable, one or more reagents
7. The proximal or receiving end
6 of the sample receiving chamber
1 can be flared funnel shaped or otherwise molded such that a sample can readily and
accurately be transferred into the sample receiving chamber
1, but this need not be the case. Alternatively a funnel shaped adaptor can be separable
and directly or indirectly engage the proximal end
6 of the sample receiving chamber
1.
[0016] The sample receiving chamber
1 can be made of suitable material such as, but not limited to, glass, ceramics, metals,
plastics, polymers, or copolymers, or any combination thereof but preferably comprises
a plastic, polymer or copolymer such as those that are resistant to breakage, such
as polypropylene, polyallomer, polycarbonate or cycloolefins or cycloolefin copolymers.
A sample receiving chamber
1 can be made by appropriate manufacturing methods, such as, but not limited to, injection
molding, blow molding, machining or press molding.
[0017] A sample can be fluid, solid or gaseous, or any combination thereof. In one aspect
of the present invention a sample can be transferred to, and flow through or be retained
in, and can subsequently be released from, the sample receiving chamber
1. Transfer of a sample into the sample receiving chamber
1 can be by various techniques such as, but not limited to pipetting, poring, decanting,
dropping or streaming. Optionally, a sample can be mixed with one or more reagents.
Mixture can occur prior to transfer into the sample receiving chamber, but preferably
the sample and one or more reagents
7 can be mixed in the sample receiving chamber
1. Reagents can include one or more salts, chelators, anticoagulants, detergents, stabilizers,
diluents, buffering agents, enzymes, cofactors, specific binding members, labels,
and the like. The one or more reagents can be compounds that facilitate analysis of
a sample, but this is not a requirement of the present invention.
[0018] In another aspect of the present invention a sample can be transferred to the sample
receiving chamber
1 by way of a sample collection device such as, but not limited to, a rod, spoon, spatula,
knife, brush,or fabric, but is preferably a swab
4. In one embodiment of the present invention a sample can be collected onto the sample
collection device, for example by dipping, submerging, soaking, dabbing, scraping,
swiping or wiping. The sample collection device with sample can then be transferred
or otherwise placed or inserted into the sample receiving chamber
1, optionally with one or more reagents in the sample receiving chamber
1 or subsequently added to the sample receiving chamber
1.
[0019] In one preferred aspect of the present invention one or more concentric or longitudinal
ribs, ridges or edges
51 can be arranged along the interior of the sample receiving chamber
1 as depicted in
FIG. 5. The one or more structures
51 can facilitate extraction of a sample from the sample receiving chamber
1 to mix with one or more reagents in the sample receiving chamber
1. For example, when a swab
4 is used to collect a sample, such as by dipping the swab head
5 into a blood sample, the swab
4 can be inserted into the sample receiving chamber
1 with one or more longitudinal ridges
51 aligned along the inside wall. By rotating the swab
4 different portions of the swab head
5 can be alternately compressed and decompressed by the one or more longitudinal ridges
51 to facilitate release of the blood into the sample receiving chamber
1.
[0020] In another embodiment one or more filters can be positioned within the sample receiving
chamber
1, preferably at or near the distal end
21 of the sample receiving chamber
1. When a sample or sample and reagent flow through, or are released from, the sample
receiving chamber
1, aggregates or particulate matter can be trapped by the one or more filters and prevented
from exiting the sample receiving chamber
1. For example, blood cells can be trapped from a whole blood sample by the one or more
filters. Filters can be composed of various materials such as, but not limited to,
paper, cellulose and cellulose derivatives, nitrocellulose, polymers, charcoal, glass
fibers, organic fibers, cotton, hair, wool, fur, or lint, or in any combination thereof.
[0021] In one aspect of the test device of the present invention the sample receiving chamber
1 is separate from the test platform
2. The distal end
21 of the sample receiving chamber
1 can engage a test platform
2, preferably at an opening or aperture
22 of the test platform
2, such that they are substantially perpendicular to each other (See for example
FIG. 2). The sample receiving chamber
1 can be inserted into an aperture
22 of the test platform 2 in order to engage the test platform
2. Insertion can be by various structures such as, but not limited to, slide, push,
snap, twist, bayonet fit, or screw the distal end
21 of the sample receiving chamber
1 into an aperture
22 of the test platform
2. For example, the aperture
22 can have a spiral path along the inner wall and threads can be formed along the external
distal region of the sample receiving chamber
1 such that they can be attached by a twisting or screwing motion. In the case of a
snap insertion a groove can be formed along the inside wall of the aperture
22 and a raised ridge can encircle the outside distal region of the sample receiving
chamber
1 such that the sample receiving chamber
1 can be slid into the aperture
22 and the ridge snaps or locks into the groove of the aperture
22. Alternatively, the aperture
22 can be encircled by a raised edge, with or without grooves or threads, over which
the sample receiving chamber
1 can be slid, snapped or screwed to engage the test platform
2. Grooves or threads can be machined into the appropriate component during manufacture
using techniques commonly used in the art. A snap or snug fit can confer a reassuring
sound or feel so that the operator is confident that the sample receiving chamber
1 and the test platform
2 have engaged properly. Optionally, one or more structures such as one or more gaskets
or one or more O-rings
65, or any combination of such structures, can be positioned at the intersection of the
sample receiving chamber
1 and the test platform
2 to reduce or prevent any leakage.
[0022] In a preferred aspect of the test device of the present invention one or more valve
structures
20 can be positioned such that the one or more valve structures can actuate flow from
the sample receiving chamber
1 into the test platform
2 of the test device. The valve structure
20 can be directly engaged to the distal or outlet end of the sample receiving chamber
1, or the sample receiving chamber
1 can itself be comprised of a valve structure, whereupon when engaged to the test
platform
2, the valve structure can actuate flow from the sample receiving chamber
1 into the test platform
2.
[0023] The valve can be of any type as recognized in the art such as, but not limited to,
a rotary, stopcock, gate, ball, needle, butterfly, pinch, bellows, piston, slide,
plug, diverter, or actuator valve. When the valve is in the closed position, as depicted
for several examples in
FIG. 4, and the sample receiving chamber
1 sufficiently vertical, a sample or sample and reagent can be retained in the sample
receiving chamber
1. When the valve is in the open position the contents of the sample receiving chamber
1 can be released, for example by gravity flow. In a preferred embodiment of the present
invention the valve structure
20 can be opened to release the contents from the distal or outlet end
21 of the sample receiving chamber
1 such that the flow can be actuated, regulated or modulated. In another aspect of
the present invention the valve mechanism
20 can be closed such that the sample or sample and one or more reagents can be retained
in the sample receiving chamber
1 for any length of time. The valve structure
20 can then be mechanically, fully or partially, opened to release the contents through
the distal or outlet end
21 of the of the sample receiving chamber
1 into the test platform
2 of the test device, optionally at a regulated or modulated rate. In a preferred embodiment
the sample receiving chamber
1 can be engaged to a second device, for example the test platform
2 of the present invention, such that opening of the valve structure
20 can release the contents into the second device. The valve structure
20 at the distal end of the sample receiving chamber
1 can be opened to release the contents by various means such as, but not limited to,
opening a stopcock or by turning, rotating, twisting or sliding the valve structure
such that the valve can be opened to allow fluid communication into the test platform
2 (see of example
FIG. 4).
[0024] An example of a sample receiving chamber
1 comprising a valve is depicted in
FIG 6. In this embodiment the sample receiving chamber
1 is comprised of a male insert
60 and female receptor
66. The female receptor
66 is a tube-like structure with a base
67 that can be engaged to an aperture
22 of a test device. The male insert
60 is cylindrical with the bottom or distal end stopped or closed off, for example during
manufacture, and having an outlet port
64 situated along the side wall
62 at the distal or lower region of the male insert
60. The male insert
60 can be introduced into the female receptor
66 such a stud
63 protruding from the side of the male insert
60 fits into a groove guide
69 of the female receptor
66. When in the closed position the stud
63 of the male insert
60 sits at the top of the upper region of the female receptor groove guide
69. In this position the outlet port
64, flanked by one or more O-rings
65 to reduce or prevent leakage, faces the inner wall of the female receptor
66 such that fluid is retained in the sample receiving chamber
1. To open the sample receiving chamber
1 valve structure an operator can rotate the upper region of the male insert
60 whereby the groove guide
69 slides the stud
63, and therefore the male insert
60, in a downward direction such that the outlet port
64 protrudes below the female receptor
66 releasing the contents of the sample receiving chamber
1 into the test platform
2, preferably onto a sample application zone
30 of a test element, preferably a test strip
3.
[0025] In another aspect of the present invention a predetermined amount of one or more
reagents can be prepackaged in the sample receiving chamber
1. In one aspect, a valve structure
20 at the distal end of the sample receiving chamber
1 can be closed and the proximal, or insertion, end
6 can be sealed by a removable or puncturable barrier, cover, or seal. In another embodiment
one or more puncturable barriers situated within the sample receiving chamber
1 can separate or sequester a predetermined volume or volumes of one or more reagents.
A removable cover can be for example a cap or screw-top. The cap or screw-top can
be made of any appropriate material such as, but not limited to, metal or plastic,
or any combination thereof. A puncturable barrier, cover or seal can be made of materials
such as, but is not limited to, plastic, foil, membrane or cellophane, or any combination
thereof. In one aspect, a puncturable seal can be at or near the proximal end of the
sample receiving chamber
1, for example recessed within the sample receiving chamber
1. A puncturable barrier, cover or seal is substantially water soluble, water permeable,
substantially air permeable or air permeable. Suitable materials for a puncturable
barrier or membrane include polymers or copolymers, such as for example polypropylene,
polycarbonate, cycloolifins, cycloolifin copolymers, foils, and plastic/foil laminates.
Alternatively the one or more reagents can be separably packaged in a breakable or
rupturable material, for example capsules, pouches, or balloons such that one or more
reagent containing packages can be added to the sample receiving chamber
1 and punctured or ruptured by a barrier rupturing device or sample collection device.
[0026] In one aspect of the present invention a puncturing device such as, but not limited
to a rod, needle, spear or spear-like structure can be inserted and withdrawn, one
or more times, at the proximal, or insertional, end
6 of the sample receiving chamber
1 such that a seal or puncturable barrier is punctured, torn, ripped or removed to
allow insertion of the sample. In another embodiment the puncturing device can be
used to rupture the one or more puncturable barriers within the sample receiving chamber
1 and a sample or sample and one or more additional reagents are inserted into the
sample receiving chamber
1. In a preferred embodiment a sample collection device can be used as the puncturing
device. In a more preferred embodiment the sample collection device with sample can
be used as the puncturing device whereby the sample and sample collection device are
inserted into the sample receiving chamber
1 and the sample can mix with one or more reagents. In another embodiment one or more
reagent containing packages, such as a capsule, pouch or balloon, that can be broken,
ruptured or torn to release the contents of the respective packages can be compromised
prior to insertion of the contents into the sample receiving chamber
1. For example a pouch can be torn and from which a reagent
7 can be transferred into the sample receiving chamber
1. Transfer can be by various techniques such as, but not limited to pipetting, poring
or dropping the one or more reagents into the proximal, or insertional, end
6 of the sample receiving chamber
1. In another example a capsule containing reagent can be positioned over the proximal
end of a sample receiving chamber
1 and crushed, such as between finger and thumb of an operator, and thereby infuse
the sample receiving chamber
1 with the reagent.
[0027] A sample receiving chamber
1 of the present invention can optionally include a key for engaging a second device,
preferably a test platform
2 of the present invention. Use of a key to engage a sample receiving chamber
1 with a test platform
2 can position a sample receiving chamber
1 and test platform
2 of the present invention such that sample, optionally mixed with one or more reagents,
can be dispensed into the appropriate area of a second device, preferably a test platform
2.
[0028] A key can be integral to a sample receiving chamber
1 of the present invention, or can be separate and can engage a sample receiving chamber
1. Preferably, a key is positioned at or near the distal end
21 of the sample receiving chamber
1. Preferably, a key can be inserted into an aperture
23 of a test platform
2 of the present invention and turned or pushed into a position that locks or fixes
the sample receiving chamber
1 and test platform
2 in position to dispense contents of the sample receiving chamber
1 into the test platform
2 and thereby onto a test element. A key can be of any shape, regular or irregular,
but preferably the shape is such that the key fits into, around or in the vicinity
or immediate vicinity of an aperture
23 of a test platform
2 of the present invention that is designed to fit the key and receive the sample.
Examples of possible key designs are depicted in
FIG. 7.
[0029] In some preferred embodiments, a key can be shaped such that a particular sample
receiving chamber
1 can be fit into a particular type of test device, or into a particular aperture
23 of a test device, such as a test platform
2. For example, a sample receiving chamber
1 of the present invention can contain one or more reagents that are specific to a
particular test for the presence of an analyte of interest. Such a sample receiving
chamber
1 can have a key of a shape that fits an analysis device, such as the test platform
2 of the present invention that performs the particular test for the analyte of interest.
In one aspect, the key of the sample receiving chamber
1 will not allow the sample receiving chamber
1 to be positioned in an analysis device or test platform
2 that tests for the presence of a different analyte. In other aspects, the key of
the sample receiving chamber
1 will allow the sample receiving chamber
1 to be positioned in one or more analysis devices, preferably one or more test platforms
2 with one or more test elements, that test for the presence of one or more analytes.
[0030] In another aspect, a test platform
2 can have one or a plurality of test areas designated for different tests. A key can
be used to specify where on the test platform
1 a sample receiving chamber
2 with a specific sample, optionally mixed with specific one or more reagents
7, can be inserted or positioned and dispensed for a specific analytical test.
[0031] In addition, an analysis device or test platform
2 that can test for the presence, amount, or quality of more than one analyte can have
sample application apertures
23 for different tests. An aperture
22 or apertures of a test platform
2 can allow the application of sample, optionally mixed with specific one or more reagents,
to specific tests. The aperture
23, or area around or in the vicinity or immediate vicinity of the aperture
23, can be of different shapes wherein the specific shape of the aperture
23, or area around or in the vicinity of the aperture
23, specifies a particular shape of key accepted at that site of a test platform
2 and therefore allows for engagement of a specific sample receiving chamber
1 at that site. For examples see
FIG. 8 and
FIG. 9. In this way, the user of a particular sample receiving chamber can avoid dispensing
sample into a test platform
2 that is not designed, or have the proper test element to test for the analyte of
interest, or at an incorrect test site in a test platform
2 having a plurality of tests.
[0032] In some preferred embodiments, a key of a sample receiving chamber
1 of the present invention can fit in, on or over a sample application aperture
23, 80 of a test device in only one orientation. For example, the key can be of a shape
that has a rounded end and a protruding end, and the sample application aperture
23 is of similar shape, such that the key can engage the analysis device only when the
protruding end of the key aligns with the elongated end of the sample application
aperture.
[0033] A key can comprise any suitable material, but preferably comprises a non-breakable
resilient plastic or polymer or copolymer such as polypropylene, polyallomer, polycarbonate
or cycloolefins or cycloolefm copolymers. A key can be made by appropriate manufacturing
methods, such as injection molding, blow molding, machining or press molding.
TEST PLATFORM
[0034] The test platform
2 of the test device of the present invention comprises a housing for one or more test
elements such as, but not limited to, a lateral flow detection device such as a test
strip 3. For examples see
FIG. 3. The test platform
2 can have at least one aperture
22 at which the distal end
21 of a sample receiving chamber
1 can directly or indirectly engage as depicted in
FIG. 2. The contents of the sample receiving chamber
1 can be released and flow into the test platform
2 through the aperture
21. Preferably the sample application area
30 of at least one test element is positioned at or near the aperture
21 of the test platform
2 such that the fluid contents of the sample receiving chamber
1 come into fluid contact with the test element.
[0035] The test platform
2 of the test device of the present invention can be made of, but not be limited to,
any suitable material, such as glass, ceramics, metals, paper, pressed cardboard,
or polymers, but preferably comprises a plastic, polymer or copolymer such as those
that are resistant to breakage, such as polypropylene, polyallomer, polycarbonate
or cycloolefins or cycloolefin copolymers. The test platform
2 can be of any shape or depth but preferably acts as a base to support the sample
receiving chamber
1 when engaged with the test platform
2.
[0036] In a preferred embodiment of the present invention the test platform
2 can directly or indirectly engage the distal portion of a sample receiving chamber
1 such that the sample receiving chamber
1 is preferably substantially perpendicular to the test platform
2. For examples see
FIG. 1 and
FIG. 2. The sample receiving chamber
1 can be received into an aperture
22 of the test platform 2 in order to engage the test platform
2. Engagement can be by various structures such as, but not limited to, slide, push,
snap, twist, bayonet fit, or screw into the aperture
22. For example, the aperture
22 can have a spiral path along the inner wall and threads can be formed along the external
distal region of the sample receiving chamber
1 such that they can be attached by a twisting or screwing motion. In the case of a
snap insertion a groove can be formed along the inside wall of the aperture
22 and a raised ridge can encircle the outside distal region of the sample receiving
chamber
1 such that the sample receiving chamber
1 can be slid into the aperture
22 and the ridge snaps or locks into the groove of the aperture
22. Alternatively, the aperture
22 can be encircled by a raised edge, with or without grooves or threads, over which
the sample receiving chamber
1 can be slid, snapped or screwed to engage the test platform
2. Grooves or threads can be machined into the appropriate component during manufacture
using techniques as known in the art. A snap or snug fit can confer a reassuring sound
or feel so that the operator is confident that the sample receiving chamber
1 and the test platform
2 have engaged properly.
[0037] In another aspect of the test device of the present invention one or more test elements,
preferably one or more test strips
3, can be housed by the test platform
2 such that the test elements are made available for use. In one embodiment the test
platform
2 has one or more recessed channels or troughs substantially along the top surface
of the test platform
2. Preferably the dimensions of such channels or trenches can accommodate a test element,
preferably a test strip
3. The one or more channels or trenches can be open
10, that is uncovered, or one or more windows can be positioned to cover the one or more
channels or trenches and test elements such that flow and visual results can be observed
in accordance with the test and the test element. A window can consist of any transparent
material, such as glass, plastic, or mylar, but is preferably break resistant. More
preferably the at least one window covering the at least one channel of the test platform
2 is moisture resistant such that the one or more test elements are shielded from external
moisture.
[0038] In another aspect, the test platform of the present invention can have one or more
apertures
22 that can receive a sample or sample and one or more reagents 7 into the test platform.
In one embodiment the sample or sample and one or more reagents can be dispensed into
an aperture
22 of the test platform
2 from a first device, preferably from a sample receiving chamber
1. In a preferred embodiment the at least one or more apertures
22 are positioned at the end of at least one channel or trench of the test platform
2 having at least one test element. More preferably the one or more apertures
22 can be at the end of the one or more channels or trenches such that a sample application
zone
30 of one or more test elements, preferably a test strip
3, is accessible to fluid communication with a sample or sample and one or more reagents
(for example see
FIG. 3. The one or more channels or trenches can be open, that is uncovered, or one or more
windows can be positioned to cover the one or more channels or trenches and test elements
such that flow and visual results can be observed in accordance with the test and
the test element.
[0039] Another embodiment of the present invention can have a test platform
2 with one or more apertures
22 leading to a common sample application region of a test element. Alternatively, a
plurality of tests strips
3 with a separate aperture
22 for each, can be housed within a single test platform
2. The test strips can be aligned in parallel (for example see
FIG. 9) or be juxtaposed to each other in any pattern. Alternatively a single aperture
22 can be associated with a plurality of test strips. For example, a single sample or
sample and reagent can be made available through a single aperture
22 to each of a plurality of test strips such that the single sample can come into fluid
communication with the test strips that can test for the presence or absence of different
analytes. The plurality of test strips can radiate from the single aperture
22 in all directions or in a confined array, or any combination thereof. A test platform
2 can have one or more apertures that can give access to the sample application region
of one or more test strips.
[0040] A test strip
3 used in context with the present invention can optionally include indicia that can
include a designation for the test to be performed using the test strip
3. Such indicia may be printed on the test strip material using methods known in the
art. Alternatively, indicia may be on other thin members, such as plastic or paper,
that are attached to the test strip
3, such as by adhesives. A test platform
2 can include one or more test strips including indicia. In the case where a test platform
2 has multiple test strips including indicia, the test strips can include reagents
and binding members for different analytes, allowing the user to test for the presence
of more than one analyte simultaneously. Test strips having indicia printed directly
thereon, or having indicia in the form of attached "sticker labels", can be assembled
into test platforms
2 in any of a large number of configurations and combinations, such that a given test
device can have a particular subset of test strips specific for the detection of a
particular subset of analytes, without changing the design of the test platform
2. In these embodiments, the test platform
2 can include one or more channels or trenches that allows the user to read the indicia
on the test strip
3.
[0041] In another aspect of the present invention the one or more apertures
22 of the test platform
2 can be shaped to receive a key that can be used to orient and/or engage a sample
receiving chamber
1 For example see
FIG. 8. In one embodiment one or more apertures
22 of a test platform
2 can be designed to accept a key engaged at the distal end of a sample receiving chamber
1 of the present invention. In some preferred embodiments, a key can be shaped such
that the distal end of a particular sample receiving chamber
1 can be fit into or at a single aperture
23 or a particular aperture
23 of at least one of several apertures of a test platform
2 as depicted in
FIG. 9. For example, a sample receiving chamber
1 of the present invention can contain a sample with one or more reagents that are
specific to a particular test for the presence of an analyte of interest. Such a sample
receiving chamber
1 can have a key of a shape that fits an aperture
23 of a test platform
2 housing a specific test element that performs the particular test for an analyte
of interest. In one aspect the key of the sample receiving chamber
1 will not allow the sample receiving chamber
1 to be positioned in the aperture
23 of a test platform
2 that links to a test element that test for the presence of a different analyte. In
other aspects, the key of the sample receiving chamber
1 will allow the sample receiving chamber
1 to be positioned in apertures
23 of one or more test platforms
2 that links to one or more test elements that test for the presence of one or more
analytes. In this case, one or more reagents mixed or supplied with a sample receiving
chamber
1 can be compatible with more than one test for more than one analyte.
TEST ELEMENT
[0042] The test element housed within the test platform
2 of the test device of the present invention can be of any test element known in the
art and preferably comprises a lateral flow detection device such as a test strip
3, preferably an immunological test strip. (For examples see
FIG. 3.) The test platform
2 of the present invention can house one or more test strips. The one or more test
strips can be of any shape and dimensions, but preferably is a rectangular test strip
3.
[0043] The test strip
3 of a test device of the present invention may comprise, at least in part, any bibulous
or non-bibulous material, such as nylon, paper, glass fiber, dacron, polyester, nitrocellulose,
polyethylene, olefin, or other thermoplastic materials such as polyvinyl chloride,
polyvinyl acetate, copolymers of vinyl acetate and vinyl chloride, polyamide, polycarbonate,
polystyrene, etc. In a preferred embodiment, at least one test strip
3 material is nitrocellulose having a pore size of at least about
1 micron, more preferably of greater than about 5 microns, or about 8-12 microns. Very
suitable nitrocellulose sheets having a nominal pore size of up to approximately 12
microns, are available commercially from, for example, Schleicher and Schuell GmbH.
[0044] A test strip
3 can include one or more materials. If a test strip
3 comprises more than one material, the one or more materials are preferably in fluid
communication as depicted in
FIG. 3B and
FIG. 3C. One material of a test strip 3 may be overlaid on another material of the test strip,
such as for example, filter paper overlaid on nitrocellulose. Alternatively or in
addition, a test strip
3 may include a region comprising one or more materials followed by a region comprising
one or more different materials. In this case, the regions are in fluid communication
and may or may not partially overlap one another.
[0045] The material or materials of the test strip
3 can be bound to a support or solid surface such as found, for example, in thin-layer
chromatography and may have an absorbent pad either as an integral part or in liquid
contact. For example, a test strip
3 may comprise nitrocellulose sheet "backed", for example with a supporting sheet,
such as a plastic sheet, to increase its handling strength. This can be manufactured
by forming a thin layer of nitrocellulose on a sheet of backing material. The actual
pore size of the nitrocellulose when backed in this manner will tend to be lower than
that of the corresponding unbacked material. Alternatively, a pre-formed sheet of
nitrocellulose and/or one or more other bibulous or non-bibulous materials can be
attached to at least one supporting sheet, such as a sheet made of polymers (see,
U.S. Patent No. 5,656,503 to May et al., issued August 12, 1997). The supporting sheet can be transparent, translucent or opaque. In the aspect of
the present invention where the support sheet is transparent, the supporting sheet
is preferably moisture impervious but can be moisture resistant or moisture pervious.
The test strip
3 can be assembled in a test platform
2 of the present invention such that the support sheet is optionally on the side of
the test strip
2 that can be viewed from the upper face of the test platform
2. In this way the test strip
2 can be viewed along an open
10 or uncovered channel of the test platform
2, and the test strip
3 is protected from contact with moisture. In another embodiment of the present invention
the test strip
3 can be viewed through a window comprised of a transparent material such as glass,
plastic, or mylar, but preferably break resistant.
[0046] In the following discussion strips of test strip
3 material will be described by way of illustration and not limitation.
[0047] Generally, test strips
3 of a test device of the present invention include a sample application zone
30 and a test results determination region
33. The test results determination region
33 can include either or both of one of more analyte detection zones
9 and one or more control zones
11. Optionally, a test strip
3 can include a reagent zone
32.
[0048] One or more specific binding members in the test results determination region
33 of the test strip
3 can be impregnated throughout the thickness of the bibulous or non-bibulous material
in the test results determination region
33 (for example, specific binding members for one or more analytes can be impregnated
throughout the thickness of the test strip material in one or more analyte detection
zones
9, and specific binding members for one or more control analytes can be impregnated
throughout the thickness of the test strip material in one or more control zones
11, but that need not be the case). Such impregnation can enhance the extent to which
the immobilized reagent can capture an analyte present in the migrating sample. Alternatively,
reagents, including specific binding members and components of signal producing systems
may be applied to the surface of the bibulous or non-bibulous material. Impregnation
of specific binding members into test strip materials or application of specific binding
members onto test strip materials may be done manually or by machine.
[0049] Nitrocellulose has the advantage that a specific binding member in the test results
determination zone
9 can be immobilized without prior chemical treatment. If the porous solid phase material
comprises paper, for example, the immobilization of the antibody in the test results
determination zone
9 can be performed by chemical coupling using, for example, CNBr, carbonyldiimidazole,
or tresyl chloride.
[0050] Following the application of a specific binding member to the test results determination
zone, the remainder of the porous solid phase material should be treated to block
any remaining binding sites elsewhere. Blocking can be achieved by treatment with
protein (for example bovine serum albumin or milk protein), or with polyvinylalcohol
or ethanolamine, or any combination of these agents. A labeled reagent for the reagent
zone
32 can then be dispensed onto the dry carrier and will become mobile in the carrier
when in the moist state. Between each of these various process steps (sensitization,
application of unlabeled reagent, blocking and application of labeled reagent), the
porous solid phase material should be dried.
[0051] To assist the free mobility of the labeled reagent when the test strip is moistened
with the sample, the labeled reagent can be applied to the bibulous or non-bibulous
material as a surface layer, rather than being impregnated in the thickness of the
bibulous material. This can minimize interaction between the bibulous or non-bibulous
material and the labeled reagent. For example, the bibulous or non-bibulous material
can be pre-treated with a glazing material in the region to which the labeled reagent
is to be applied. Glazing can be achieved, for example, by depositing an aqueous sugar
or cellulose solution, for example of sucrose or lactose, on the carrier at the relevant
portion, and drying (see,
U.S. Patent No. 5,656,503 to May et al., issued August 12, 1997). The labeled reagent can then be applied to the glazed portion. The remainder of
the carrier material should not be glazed.
[0052] The reagents can be applied to the carrier material in a variety of ways. Various
"printing" techniques have previously been proposed for application of liquid reagents
to carriers, for example micro-syringes, pens using metered pumps, direct printing
and ink-jet printing, and any of these techniques can be used in the present context.
To facilitate manufacture, the carrier (for example sheet) can be treated with the
reagents and then subdivided into smaller portions (for example small narrow strips
each embodying the required reagent-containing zones) to provide a plurality of identical
carrier units.
[0053] In embodiments where the analyte is detected by a signal producing system, such as
by one or more enzymes that specifically react with the analyte, one or more components
of the signal producing system can be bound to the analyte detection zone
9 of the test strip material in the same manner as specific binding members are bound
to the test strip material, as described above. Alternatively or in addition, components
of the signal producing system that are included in the sample application zone
30, the reagent zone
32, or the analyte detection zone
9 of the test strip
3, or that are included throughout the test strip
3, may be impregnated into one or more materials of the test strip
3. This can be achieved either by surface application of solutions of such components
or by immersion of the one or more test strip materials into solutions of such components.
Following one or more applications or one or more immersions, the test strip material
is dried. Alternatively or in addition, components of the signal producing system
that are included in the sample application zone
30, the reagent zone
32, or the analyte detection zone of the test strip
9, or that are included throughout the test strip
3, may be applied to the surface of one or more test strip materials of the test strip
3 as was described for labeled reagents.
Sample Application Zone
[0054] The sample application zone
30 is an area of a test strip
3 where a sample, such as a fluid sample, such as a biological fluid sample such as
blood, serum, saliva, or urine, or a fluid derived from a biological sample, such
as a throat or genital swab, is applied. The sample application zone
30 can include a bibulous or non-bibulous material, such as filter paper, nitrocellulose,
glass fibers, polyester or other appropriate materials. One or more materials of the
sample application zone
30 may perform a filtering function, such that large particles or cells are prevented
from moving through the test strip
3. The sample application zone
30 can be in direct or indirect fluid communication with the remainder of the test strip
3, including the test results determination zone
9. The direct or indirect fluid communication can be, for example, end-to-end communication
as depicted in
FIG. 3C, overlap communication as depicted in
FIG. 3B and
FIG. 3C, or overlap or end-to-end communication that involves another element, such as a fluid
communication structure such as filter paper.
[0055] The sample application zone
30 can also include compounds or molecules that may be necessary or desirable for optimal
performance of the test, for example, buffers, stabilizers, surfactants, salts, reducing
agents, or enzymes.
Reagent Zone
[0056] The test strip
3 can also include a reagent zone
32 where reagents useful in the detection of an analyte can be provided immobilized
(covalent or non-covalent immobilization) or not immobilized, particularly when in
a fluid state. The reagent zone
32 can be on a reagent pad, a separate segment of bibulous or non-bibulous material
included on the test strip
3, or it can be a region of a bibulous or non-bibulous material of a test strip
3 that also includes other zones, such as an analyte detection zone
9. In one aspect of the invention, the reagent zone
32 can include a labeled specific binding member, such as antibodies or active fragments
thereof attached or linked to a label. Such labeled specific binding members can be
made using methods known in the art. The specific binding members can bind an analyte
and/or can bind a control compound.
[0057] In one preferred example involving detection of hCG, the reagent zone
32 includes two populations of colored beads. One population of colored beads is attached
to an anti-rabbit IgG antibody or active fragment thereof and the other population
of colored beads is attached to an anti-hCG beta chain antibody or active fragment
thereof. The labeled anti-rabbit IgG antibody or antibody fragment is used for visual
detection of a signal in the control zone
11 of the test strip
9. A color signal in the control zone
11 indicated that the sample has passed through the detection zone
9. The labeled anti-hCG beta chain antibody or fragment thereof provides a visual signal
in the detection zone
9 indicating the presence of hCG in the sample.
[0058] Other preferred embodiments are having anti-(drug of abuse) antibodies or active
fragments thereof bound to a population of colored beads. More than one population
of beads can be used as in the forgoing example to provide a visual signal in the
detection zone
9 and a second visual signal in the control zone
9. The two populations of beads can be the same or different colors or be provided as
a mixture of colors. Alternatively or in addition, different populations of beads
bound to different antibodies or antibody fragments can be used to indicate the presence
of more than one analyte in a sample by producing one or more visual signals in one
or more detection zones
9.
[0059] In another aspect of the invention, the reagent zone
32 includes the analyte or an analyte analog bound to a population of colored beads.
In this case, the analyte in the sample competes with the labeled analyte or analyte
analog provided in the reagent zone
32 for binding to a specific binding member in the test results determination zone.
A reduced visual signal in comparison with a control sample lacking analyte indicates
the presence of analyte in the sample. More than one population of beads can be used
as in the forgoing examples to provide a visual signal in the analyte detection zone
9 and a second visual signal in the control zone
11. Alternatively or in addition, different populations of beads bound to different analytes
or analyte analogs can be used to indicate the presence of more than one analyte in
a sample by producing one or more visual signals in one or more detection zones
9.
[0060] Preferred labels are beads such as metal particles, such as gold, or polymeric beads,
such as colored beads, or particles of carbon black. Other labels include, for example,
enzymes, chromophores or fluorophores such as they are known in the art, particularly
in immunoassays, or later developed. The populations of beads are provided in powdered
form on the reagent zone
32, which can include a bibulous material, such as filter paper, glass fibers, nylon,
or nitrocellulose. These reagents are reversibly bound to the reagent zone
32 because they can be mobilized when placed in contact with a fluid, such as a fluid
sample passing along a test strip
3.
[0061] In another embodiment of the invention, the reagent zone
32 can include components of a signal producing system, for example, catalysts, such
as enzymes, cofactors, electron donors or acceptors, and/or indicator compounds.
[0062] The reagent zone
32 can also include compounds or molecules that may be necessary or desirable for optimal
performance of the test, for example, buffers, stabilizers, surfactants, salts, reducing
agents, or enzymes.
Test Results Determination Zone
[0063] The test results determination zone includes immobilized or not immobilized reagents
that can detect the presence of the analyte being tested for, such as but not limited
to, drugs of abuse, hormones, metabolites, and antibodies. Such reagents are preferably
in a dry state and can be covalently immobilized, non-covalently immobilized, or not
immobilized in a fluid state. The test result determination zone can include either
or both of one or more analyte detection zones
9 and one or more control zones
11.
[0064] Depending on the particular format and analyte being tested for, a variety of reagents
can be provided at the test results determination zone. For example, the test results
determination zone can include specific binding members such as antibodies, enzymes,
enzymatic substrates, coenzymes, enhancers, second enzymes, activators, cofactors,
inhibitors, scavengers, metal ions, and the like. One or more of the reagents provided
at the test results determination zone can be bound to the test strip material. Test
strips 3 including such reagents are known in the art and can be adapted to the test
device of the present invention.
[0065] In a preferred aspect of the present invention, the one or more analyte detection
zones
9 of the test results determination zone include one or more immobilized (covalently
or non-covalently immobilized) specific binding members that bind with one or more
analytes of interest, such as one or more drugs, hormones, antibodies, metabolites,
or infectious agents, when the analytes are also bound by specific binding members
bound to a label as are provided in the reagent zone
32. Thus, in embodiments where the reagent zone
32 contains one or more specific binding members for the analyte, the specific binding
members of the reagent zone
32 and analyte detection zone
9 should bind with different epitopes on the analyte being tested for. For example,
when a labeled specific binding member in the reagent zone
32 binds with the beta-chain of hCG, then the immobilized specific binding member in
the analyte detection zone
9 should bind with another area of hCG, such as the alpha-chain of hCG. Thus, when
hCG is present in the sample, the hCG will bind the labeled anti-beta hCG which carried
along to the test result determination zone at the analyte detection zone
9 which binds with the immbolized anti-alpha hCG to provide a visual readout at that
locus.
[0066] The analyte detection zone
9 can include substrates which change in an optical property (such as color, chemiluminescence
or fluorescence) when an analyte is present. Such substrates are known in the art,
such as, but not limited to, 1,2-phenylenediamine, 5-aminosalicylic acid, 3,3',5,5'tetra
methyl benzidine, or tolidine for peroxidase; 5-bromo-4-chloror-3-indolyl phosphate/nitroblue
tetrazolium for alkaline phosphatase and 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside,
o-nitrophenyl-beta-D-galactopyranoside, napthol-AS-BI-beta-D-galactopyranoside, and
4-methyl-umbelliferyl-beta-D-galactopyranoside for beta galactosidase.
[0067] In embodiments where an analyte is detected by a signal producing system, one or
more components of the signal producing system, such as enzymes, substrates, and/or
indicators, can be provided in the analyte detection zone
9. Alternatively, the components of the signal producing system can be provided elsewhere
in the test strip
3 and can migrate to the analyte detection zone
9.
[0068] Optionally, the test results determination zone can include a control zone
11. The control zone
11 can be upstream from, downstream from, or integral with the analyte detection zone
9 of the test result determination zone. In the latter case, when analyte and control
give a positive reaction, the control zone
11 and analyte detection zone
9 can form an indicia, such as a "+" sign for a positive reaction and a "-" sign for
a negative reaction based on the particular format of the assay.
[0069] The control zone
11 provides a result that indicates that the test on the test strip
3 has performed correctly. In one preferred aspect of the present invention, the reagent
zone
32 includes a specific binding member that binds with a known analyte different from
the analyte being tested for. For example, a rabbit-IgG may be provided in the reagent
zone
32. The control zone
11 can include immobilized (covalently or non-covalently) anti-rabbit-IgG antibody.
In operation, when the labeled rabbit-IgG in the reagent zone
32 is carried to the test result determination zone and the control zone
11 therein, the labeled rabbit-IgG will bind with the immobilized an anti-rabbit-IgG
and form a detectable signal.
[0070] The control zone
11 can include substrates which change in an optical property (such as color, chemiluminescence
or fluorescence) when a control substance is present.
[0071] In one aspect of the present invention, a test strip
3 can include an adulteration control zone that is capable of detecting an adulteration
analyte or an adulteration indicator. Such an adulteration control zone can be in
addition to or in place of a control zone
11 or a test results determination zone
9 as described herein. In one aspect of the present invention, the test strip
3 can include an adulteration control zone and a control zone
11 and can optionally detect another analyte such as a drug. In the case where a test
strip
3 includes an adulteration control zone and a control zone
11, but does not detect another analyte, the test strip
3 can be used as a separate control strip, which can be provided in a separate channel
of a the test platform
2 of the present invention.
[0072] The adulteration control zone can detect an analyte using any appropriate method,
such as specific binding methods or using chemical detection methods. These types
of detection methods are known in the art and are described herein. For example, specific
binding methods such as antibody detection methods are described herein. Also, methods
to detect an analyte using signal detection methods using chemical or enzymatic methods
are also described herein.
[0073] Adulteration control zones preferably detect the presence or amount of an analyte
that reflects sample adulteration, such as adulteration by dilution, such as substitution
or addition of materials from another species, subject or non-human source to a sample
or by the addition of an altering agent. Depending on the monitoring of sample acquisition,
sample chain of custody and sample preparation, the need for adulteration controls
can be different. For example, blood, serum or plasma samples tend to be more difficult
for a subject from which such a sample is taken from to adulterate because such samples
tend to be drawn by a phlebotomist or other health-care professional and the chain
of custody for such samples tend to be relatively rigorous. On the other hand, samples
of urine or other bodily fluids tend to be less stringently controlled, but that need
not be the case. The choice of adulteration controls can be chosen based on the particular
circumstances for sample collection and chain of title as appropriate.
[0074] An appropriate adulteration control for different sample types, such as serum, blood,
saliva or urine, can be chosen by the skilled artisan. For example, preferred analytes
for blood or blood derived sample dilution include but are not limited to hematocrit,
protein concentration, hemoglobin (particularly for red blood cell lysis) and analytes
for urine or urine derived sample dilution include but are not limited to creatine.
Preferred analytes for blood or blood derived sample species include but are not limited
to cell-surface antigens or immunoglobulins of any class or subclass, such as IgG,
IgM, IgA, IgE or IgD and and analytes for urine or urine derived sample species include
but are not limited to cell-surface antigens or immunoglobulins of any class or subclass,
such as IgG, IgM, IgA, IgE or IgD and analytes for urine or urine derived sample subject
include but are not limited to hormones such as testosterone, estrogen or cell surface
antigens. Preferred analytes for adulterants for blood or blood derived samples include
but are not limited to pH, hemoglobin and nitrites. Preferred analytes for adulterants
include, but are not limited to pH and the adulterants or their derivatives, such
as break down products, or derivatives in the sample based on the action of the adulterant,
such as the presence or absence of analytes normally present in the sample in the
absence of an adulterant or break down products or altered analytes based on the action
of an adulterant. Preferred adulterants include, but are not limited to hypochlorite
(bleach), chlorine, gluteraldehyde, soap, detergent, Drano (TM), Visine (TM), Golden
Seal Tea (TM), citrus products such as juice such as lemon or lime juice, nitrate,
Urine Luck (TM) and pyridinium chlorochromate.
[0075] Adulteration control zones can be made using methods known in the art and described
herein, such as for making a test results determination zone to detect an analyte.
The adulteration control zone can be thought of as a test results determination zone
for an adulteration analyte and thus the reagent zone can include appropriate reagents
for performing an assay for an adulteration analyte. For example, a test strip 3 can
include detectably labeled rabbit anti-human IgG and the adulteration control zone
can include immobilized goat anti-human IgG antibodies. Thus, in operation of the
test strip 3, the sample adulteration control zone having the detectable label bound
thereto would indicate that the sample contains human IgG and thus is presumptively
of human origin. If, for example, a supposedly human serum sample was used as a sample
in such a test strip 3, the lack of a detectable label in the sample adulteration
control zone would indicate that the sample was not of human origin and thus would
not be a valid test. In those circumstances, the test results would indicate that
the sample was adulterated, such as providing a serum sample from another species
or by altering the sample such that human IgG was degraded or otherwise not present.
Adulteration tests can be quantitative or semi-quantitative such that dilution of
a sample of human origin would result in a readout having less detectable label than
a standard range for undiluted samples. Adulteration tests can be used to detect one
or more adulterants in one or more test strips. For example, a single adulteration
test strip can detect one or more adulterants.
[0076] In one preferred aspect of the present invention, the test strip
3 can include a results determination zone that includes a control zone
11 and a analyte detection zone
9, and a sample adulteration control zone. In another aspect of the present invention,
a test strip
3 can include a results determination zone that optionally includes a control zone
11, and optionally an adulteration control zone. A second test strip
3 can include an adulteration control zone and optionally a control zone
11. Preferably, this second test strip
3 includes both an adulteration control zone and a control zone
11, but that need not be the case. In the instance where one or more first test strips
can be used to detect an analyte other than an adulteration analyte and one or more
second test strips can be used to detect an adulteration analyte, the test strips
can be provided in a single test platform
2 of the present invention, such as a multi-channel test platform
2.
Orientation of Zones
[0077] The various zones of a test strip
3, including a sample application zone
30, one or more reagent zones
32, and one or more test result determination zones, including one or more analyte detection
zones
9 and optionally including one or more control zones
11 and one or more adulteration zones, can be on a single strip of material, such as
filter paper or nitrocellulose, or can be provided on separate pieces of material.
The different zones can be made of the same or different material or a combination
of materials, but preferably are selected from bibulous materials, such as filter
paper, fiberglass mesh and nitrocellulose. The sample application zone
30 preferably includes glass fibers, polyester or filter paper, the one or more reagent
zones
32 preferably include glass fibers, polyester or filter paper and the test results determination
zone, including one or more analyte detection zones
9 and optionally including one or more control zones
11, preferably include nitrocellulose.
[0078] Optionally, a fluid absorbing zone is included. The fluid absorbing zone preferably
includes absorbant paper and is used to absorb fluid in a sample to drive fluid from
the sample application zone
30 through the reagent zone
32 and the detection zone.
[0079] Preferably, the zones are arranged as follows: sample application zone
30, one or more reagent zones
32, one or more test results determination zones, one or more control zones
11, one or more adulteration zones, and fluid absorbing zone. If the test results determination
zone includes a control zone
11, preferably it follows the analyte detection zone
9 of the test result determination zone. All of these zones, or combinations thereof,
can be provided in a single strip of a single material. Alternatively, the zones are
made of different materials and are linked together in fluid communication. For example,
the different zones can be in direct or indirect fluid communication. In this instance,
the different zones can be jointed end-to-end to be in fluid communication (for example
see
FIG. 3C), overlapped to be in fluid communication (for example see
FIG. 3B), or be communicated by another member, such an joining material, which is preferably
bibulous such as filter paper, fiberglass or nitrocellulose. In using a joining material,
a joining material may communicate fluid from end-to-end joined zones or materials
including such zones, end-to-end joined zones or materials including such zones that
are not in fluid communication, or join zones or materials that include such zones
that are overlapped (such as but not limited to from top to bottom) but not in fluid
communication.
[0080] When and if a test strip
3 includes an adulteration control zone, the adulteration control zone can be placed
before or after the results determination zone. When a control zone
11 is present in the results determination zone on such a test strip
3, then the adulteration control zone is preferably before the control zone, but that
need not be the case. In the aspect of the present invention where a test strip is
a control test strip for the determination of an adulteration analyte and/or a control,
then the adulteration control zone can be placed before or after the control zone,
but is preferably before the control zone.
FLUID COMMUNICATION
[0081] In a preferred aspect of the test device of the present invention the sample receiving
chamber
1 with sample or sample and one or more reagents is engaged with the test element such
that the distal, or outlet end
21 of the sample receiving chamber
1 is inserted or otherwise affixed to or within an aperture
22 of the test platform
2. The contents of the sample receiving chamber
1 can be released into the aperture
22 of the test platform
3 and comes into fluid contact with at least one test element, preferably the sample
application zone of a test strip
3. The sample or sample and one or more reagents flow along the test strip by wicking
action and can optionally come into fluid contact with specific one or more anlyte,
antibody or labeled member for an analyte, or a combination thereof, which can be
freely mobile within the bibulous material when in the moist state. In a preferred
aspect of the present invention the test contents of the sample or sample and one
or more reagents and optional elements of the test strip
3 come into fluid contact with a detection zone of the test strip that can indicate
the presence or absence for a specific analyte in the sample.
II A METHOD OF DETECTING AN ANALYTE IN A SAMPLE
[0082] The device of the present invention can be used to collect a sample, transfer the
sample to a sample receiving chamber
1 and optionally mix the sample with one or more reagents
7. The sample or sample and one or more reagents can then be conducted to a test element
within a test platform
2 to detect one or more analytes in the sample, preferably a sample application zone
30 of a test strip
3. The sample can be gaseous, liquid, colloidal or solid. Examples of liquid or fluid
samples that can be inserted into the sample receiving chamber
1 of the present embodiment can include water including pond, lake, stream, or "runoff'
water, or biological samples such as blood, serum, saliva, or urine. Other biological
samples can include fecal samples, and throat or genital swabs. Examples of solid
samples can include such materials as dirt, grains, granules, powders or pellets.
[0083] To collect a sample into the sample receiving chamber
1 a fluid or colloidal sample can be inserted via various techniques, for example pipeting,
pouring or by use of a dropper. Alternatively a sample collection device can be used
to collect a sample and transfer the sample into the sample receiving chamber
1. The sample collection device can be of different structures but is preferably a swab
4. The swab
4 can be used to collect the sample onto the swab head
5 by different embodiments such as for example dipping, swiping or swabbing. The swab
4 with sample can be inserted into the sample receiving chamber
1 that can optionally contain one or more reagents or can have one or more reagents
7 added to the sample receiving chamber
1 during or after insertion of the sample collection device and sample. In each scenario
the sample can be mixed or otherwise extracted into the sample receiving chamber
1 by an extraction solution that can include, for example, the one or more diluents,
buffers or reagents. Optionally, one or more structures, for example one or more ribs
or edges
51 located longitudinally within the inner wall of the sample collection device can
facilitate extraction of the sample from a swab
4 by rotating the swab
4 such the one or more ribs or edges
51 and the one or more spaces in-between alternatively compress and decompress different
portions of the swab head 5 to release sample into the sample receiving device.
[0084] The sample receiving chamber
1 can be separate from the test platform
2 and can be engaged to an aperture
22 of the test platform
2. The sample receiving chamber
1 is in a vertical position and essentially perpendicular to the test platform
2. When separate, the sample collection device and sample and optional one or more reagents,
can be added to the sample receiving chamber
1 before or after the sample receiving chamber
1 is engaged with the test platform
2.
[0085] The sample receiving chamber
1 can be engaged to the test platform
2 by various techniques, for example the sample receiving chamber
1 can be slid, screwed or snapped into an aperture
22 of the test platform
2. Optionally, the sample receiving chamber
1 can be oriented and locked into position with the test platform
2 using a key structure. The user positions the distal end of the sample receiving
chamber
1 into an aperture
23 of the test platform
2 such that the key fits into an aperture
23 designed to receive the key, and optionally locks the sample receiving chamber
1 into place. Alternatively an aperture
22 of the test platform
2 can be encircled by a raised edge, with or without grooves or threads, over which
the sample receiving chamber
1 can be slid or snapped or screwed onto the raised edge.
[0086] The contents of the sample receiving chamber
1 can be contained and allowed to mix or incubate for a specific amount of time. To
allow for containment and incubation the mixture can be prevented from flowing out
of the distal end (the end that engages the test platform) of the sample receiving
chamber
1 by a mechanical structure, for example a closed valve
20. Flow of the contents of the sample receiving chamber
1 can be released in a regulated fashion into an aperture
22 of the test platform
2 by opening, fully or partially, a valve
20 at the distal end of the sample receiving chamber. The valve can be of any type known
in the art. For example a valve can align, or partially align, openings by a twisting
or sliding mechanism, or by a stopcock (for examples see
FIG. 4), whereby the contents can be released from the sample receiving chamber
1 in a controlled or regulated manner.
[0087] Optionally, a filtering device can be located within the sample receiving chamber
1 whereby, upon release of the contents by opening a valve, the filter can filter out
unwanted aggregates or particulates from the sample or sample and reagent or reagents
entering the test platform
2.
[0088] The test platform
2 of the present invention can house a test element, preferably an immunological test
strip
3. Thereby the test device of the present invention can be used to determine whether
a specific analyte is present in a sample. The analyte of interest can be of various
kinds, for example a biological moiety, for example a antibody or surface antigen
or a hormone such as hCG (human chorionicgonadotropin); a drug or chemical moiety;
or an etiological agent or extract from an etiological agent such as Strep (
Streptococcus) or HIV (human immunodeficiency virus). The sample application zone
30 of one or more test strips
3 can be positioned immediately below or in the vicinity of an aperture
22 of the test platform
2. The user can release the contents of the sample receiving chamber
1, optionally in a controlled or actuated manner, and onto the sample application zone
30 of the one or more test strips
3. The sample and sample and reagent travels by capillary flow along the immunochromatographic
test strip
3 and dependent on the test strip
3 used the presence or absence of an analyte in the sample can be determined by the
presence or absence of a visual line in the detection zone
9 of a test strip
3 as viewed through an opening
10 or window on the test platform
2.
EXAMPLES
EXAMPLE 1: METHOD OF USING DEVICE FOR DISEASE DETECTION: STREP-A
[0089] A throat specimen is obtained from a patient exhibiting signs and symptoms of pharyngitis
using a standard size rayon or dacron swab. The tonsil area of the throat is swabbed.
The sample receiving chamber of the test device is seated on the test platform housing
a lateral flow test strip device. Four drops or approximately 160 microliters of Reagent
A (2 molar sodium nitrate) and four drops, approximately 160 microliters of Reagent
B (0.2 molar acetic acid), are added to the extraction device. The swab containing
the throat specimen is inserted into the sample receiving chamber and rotated in a
back and forth motion for about 10 seconds. The swab is then allowed to incubate in
this solution for 60 seconds. After this time has elapsed the valve structure is actuated,
with the swab still remaining in the sample receiving chamber. The liquid contents
of the sample receiving chamber, equal to approximately 200 micoliters, is transferred
to the sample pad of the test device configured to detect Strep-A antigen. Sample
flow is initiated on the test device by capillary action and the result of the test
is viewed through the test result window 5 minutes after actuating the extraction
device valve.
EXAMPLE 2: METHOD OF USING DEVICE FOR DISEASE DETECTION: CHLAMYDIA
[0090] Endocervical specimens is collected using either rayon or dacron swabs with plastic
shafts or a cytobrush. A key structure on a sample receiving chamber of the test device
is locked into the corresponding key receptor located on the test platform housing
a lateral flow test strip device. One hundred and fifty (150) microliters of 1 normal
potassium hydroxide is placed into the sample receiving chamber of the device. The
swab or brush is placed into the chamber, rotated for 10-20 seconds and allowed to
incubate for 5 minutes. After this time, 150 microliters of 1 molar acetic acid containing
0.1% of Tween-20 are added to the chamber. The swab or brush is rotated for an additional
10-20 seconds. The valve structure is actuated with the swab or brush still remaining
in the extraction device. The liquid contents of the extraction chamber, approximately
150-250 microliters, depending on whether a swab or brush was used, are filtered through
a 1 micron filter located in the bottom of the sample receiving chamber, and are transferred
to the sample pad of the test device configured to detect Chlamydia antigen. The swab
or brush is removed from the device and disposed of as hazardous waste. Sample flow
is initiated on the test device by capillary action and the result of the test are
viewed through the test result window 10 minutes after actuating the sample receiving
chamber valve.
EXAMPLE 3: METHOD OF USING DEVICE FOR DETECTION OF GENETICALLY MODIFIED CROPS: BTK
PROTEIN
[0091] To determine if corn seed, or a corn crop has been genetically modified to produce
Bacillus thuringiensis subsp.
Kurstaki (BtK) protein, randomly select 5 to 10 grams of corn kernels from the seed supply
or from various heads of corn. Thoroughly grind the sample to ensure homogeneity.
Transfer a portion of the ground sample to the sample receiving chamber of the test
device until the sample fills the extraction chamber to 3/4 of capacity. Add 500 microliters
of normal saline. Allow this ground corn-normal saline mixture to incubate for 2 minutes.
Transfer the sample receiving chamber to the test platform being careful not to spill
contents. Seat the key structure of the sample receiving chamber onto the corresponding
key receptor located on the test platform housing a lateral flow test strip device
configured to detect BtK protein. Actuate the valve structure to allow the liquid
contents to flow from the sample receiving chamber, through the 5 micron and 1 micron
filters located in the bottom of the sample receiving chamber onto the sample pad
of the lateral flow test strip device. This volume may vary with corn variety and
the granularity of the ground corn. After 5 minutes, determine the test result through
the result window. The control line preferably is present to indicate that proper
sample flow has occurred.
EXAMPLE 4: METHOD OF USING DEVICE FOR FOOD TESTING: CLOSTRIDIUM (LIQUID SAMPLES)
[0092] To check if clostridium is present in a liquid source, first seat the key structure
of the sample receiving chamber of the test device into the corresponding key receptor
located on the test platform housing a lateral flow test strip device. Add 250 microliters
of sample to the sample receiving chamber, followed by 50 microliters of 500 millimolar
sodium phosphate buffer, pH 7.4 containing 9 grams/liter sodium chloride, 1 gram/liter
bovine serum albumin and 5 milligrams/liter EDTA. Allow this solution to incubate
for 30 seconds. Actuate the valve structure to allow the liquid contents to flow from
the sample receiving chamber, through the 5 micron and 1 micron filters located in
the bottom of the sample receiving chamber onto the sample pad of the lateral flow
test device configured to detect Clostridium antigen. Approximately 250 to 300 microliters
of sample transfer onto the sample pad. After 15 minutes, determine the test result
through the result window. The control line is preferably present to indicate that
proper flow has occurred.
[0093] All headings are for the convenience of the reader and should not be used to limit
the meaning of the text that follows the heading, unless so specified.