CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional Patent Application No. 60/140,215,
filed June 22, 1999, which is hereby incorporated herein by reference in its entirety
for all purposes.
BACKGROUND OF THE INVENTION
[0002] Microfluidic devices and systems are gaining wide acceptance as alternatives to conventional
analytical tools in research and development laboratories in both academia and industry.
This acceptance has been fueled by rapid progress in this technology over the last
several years.
[0003] The rapid progress in this field can best be illustrated by analogy to corresponding
developments in the field of microelectronics. In the field of chemical analysis,
as in microelectronics, there is a considerable need for integration of existing stationary
laboratory installations into portable systems and thus a need for miniaturization.
A survey of the most recent developments in the field of microchip technology can
be found in a collection of the relevant technical literature, edited by A. van den
Berg and P. Bergveld, under the title of "Micro Total Analysis Systems," published
by Kluwer Academic Publishers, Netherlands, 1995. The starting point for these developments
was the already established method of "capillary electrophoresis". In this context,
efforts have already been made to implement electrophoresis on a planar glass micro-structure.
[0004] Microfluidic technologies have begun to gain acceptance as commercial research products,
with the introduction of the Agilent 2100 Bioanalyzer and Caliper LabChip® microfluidic
systems. With the advent of such commercial products, it becomes more important that
users be allowed more flexibility and value for their research money, allowing broader
applicability of these systems. The present invention is directed to meeting these
and a variety of other needs.
[0005] In an article which is reproduced in the above-mentioned collection of relevant technical
literature. by Andreas Manz et al, the above-mentioned backgrounds are extensively
described. Manz et al. have already produced a microchip consisting of a layering
system of individual substrates, by means of which three-dimensional material transport
was also possible.
[0006] Through production of a micro-laboratory system on a glass substrate, the above-mentioned
article also described systems which utilized a silicon-based micro-structure. On
this basis, integrated enzyme reactors, for example for a glucose test, micro-reactors
for immunoassays and miniaturized reaction vessels for a rapid DNA testing have allegedly
been carried out by means of the polymerase chain reaction method.
[0007] A microchip laboratory system of the above type has also been described in US patent
5,858,195, in which the corresponding materials are transported through a system of
inter-connected conduits, which are integrated on a microchip. The transport of these
materials within these conduits can, in this context, be precisely controlled by means
of electrical fields which are connected along these transport conduits. On the basis
of the correspondingly enabled high-precision control of material transport and the
very precise facility for metering of the transported bodies of material, it is possible
to achieve precise mixing, separation and/or chemical or physicochemical reactions
with regard to the desired stoichiometrics. In this laboratory system, furthermore,
the conduits envisaged in integrated construction also exhibit a wide range of material
reservoirs which contain the materials required for chemical analysis or synthesis.
Transport of materials out of these reservoirs along the conduits also takes place
by means of electrical potential differences. Materials transported along the conduits
thus come into contact with different chemical or physical environments, which then
enable the necessary chemical or physicochemical reactions between the respective
materials. In particular, the devices described typically include one or several junctions
between transport conduits, at which the inter-mixing of materials takes place. By
means of simultaneous application of different electrical potentials at various material
reservoirs, it is possible to control the volumetric flows of the various materials
by means of one or several junctions. Thus, precise stoichiometric metering is possible
purely on the basis of the connected electrical potential.
[0008] By means of the above-mentioned technology, it is possible to perform complete chemical
or biochemical experiments using microchips tailor-made for the corresponding application.
In accordance with the present invention, it is typically useful for the chips in
the measurement system to be easily interchangeable and that the measurement structure
be easily adapted to various microchip layouts. In the context of electrokinetically
driven applications, this adaptation first typically relates to the corresponding
arrangement of reservoirs and the electrical high voltages required for transportation
of materials on the chip and to the corresponding application of these voltages to
the microchip. For that reason, a laboratory environment of this type typically includes
leading of electrodes to the corresponding contact surfaces on the microchip, and
arrangements for the feeding of materials to the above-mentioned reservoirs. In this
context it must particularly be taken into account that the microchips exhibit dimensions
of only a few millimeters up to the order of magnitude of a centimeters, and are thus
relatively difficult to handle.
SUMMARY OF THE INVENTION
[0009] In a first aspect, the present invention provides a system for analysis or synthesis
of materials. The system comprises a first physical unit with a mounting region for
receiving a microfluidic device. At least one second physical unit is spatially separated
from the first physical unit and comprises a material transport system that includes
at least a first interface component. The first physical unit and second physical
unit are oriented with respect to each other whereby the material transport system
provides a potential to the microfluidic device through the first interface component
to transport material through the microfluidic device. The first interface component
is removable from the second physical unit.
BRIEF DESCRIPTION OF THE FIGURES
[0010]
Figure 1 schematically illustrates the functional components required for a laboratory
microchip system, illustrated in block diagram form;
Figure 2 schematically illustrates a laboratory microchip for utilization in a system
according to the invention;
Figure 3 schematically illustrates an overview diagram of a first exemplary embodiment
of the system according to the invention;
Figure 4 schematically illustrates a block diagram corresponding to Figure 3 of a
second exemplary embodiment of the system according to the invention;
Figure 5a-5d schematically illustrate a sequence of images for illustration of the
operation of a preferred embodiment of the invention, where a module unit according
to the invention is implemented as an interchangeable cartridge;
Figure 6a and 6b schematically illustrate an embodiment of the system according to
the invention where two physical units are inter-connected by means of a hinge connection.
DETAILED DESCRIPTION OF THE INVENTION
I. Microchip Laboratory Systems
[0011] The present invention relates in general to microchip laboratory systems used in
the controlled implementation of chemical, physicochemical, physical, biochemical
and/or biological processes. More specifically the present invention relates to microchip
laboratory systems for the analysis or synthesis of materials, and particularly fluid
borne materials, within a microfluidic device or structure, by electrical, electromagnetic
or similar means. In particular, the invention relates to a system for the operation
and handling of a laboratory microchip. In general, the invention comprises a means
or region for mounting of the microchip and means or interface for providing a potential
required for the microfluidic transportation of materials on the microchip. As used
herein, the term "potential" generally refers to an energy potential that may be supplied
by, e.g., electrical sources, pressure sources, thermal sources or the like. The region
for mounting the microchip is typically arranged within a first physical unit, e.g.,
a base unit, and is configured to receive the microfluidic device, e.g., by means
of a well, barrier or barriers, slots, or other structural features that allow the
microfluidic device to be fittedly placed and/or positioned on the mounting region.
The at least first supply system or means is arranged within a spatially separate
second physical unit, e.g., a cover unit, whereby the first physical unit and the
at least second physical unit are oriented with respect to each other, e.g., they
can be fit together, to allow for operation of the microchip, e.g., by interfacing
the supply system with the microfluidic device. Generally speaking, a supply system
may supply potential, or materials or a combination of the two to the microfluidic
device.
[0012] The operational components typically used for the microchip systems described herein
are schematically illustrated in Figure 1. These are mainly subdivided into the components
relating to material transport or flow
1, and those which represent the information flow
2 arising upon execution of a test. Material flow
1 typically includes sampling operations
3 and operations for transporting
4 materials on the chip, as well as optional operations for treatment or pretreatment
5 of the materials to be examined. Furthermore, a sensor system
6 is typically employed to detect the results of a test, and optionally to monitor
the material flow operations, so that adjustments can be made in controlling material
flow using the control system. One example of the control mechanism is shown as control
electronics
7.
[0013] Data obtained in the detection operation 6 and 6' is transferred typically to the
signal processing
8 operation so that the detected measurement results can be analyzed. A priority objective
in the design of such microchip systems is the provision of function units/modules
corresponding to the above-mentioned functions and the establishment of suitable interfaces
between individual modules. By means of a suitable definition of these interfaces,
it is possible to achieve a high degree of flexibility in adaptation of the systems
to various microchips or experimental arrangements. Furthermore, on the basis of such
a strictly modular system structure, it is possible to achieve the most extensive
level of compatibility between various microchips and/or microchip systems.
[0014] Further incentives for miniaturization in the field of chemical analysis include
the ability and desirability to minimize the distance and time over which materials
are transported. In particular, the amount of time and distance required to transport
materials between the sampling of the materials and the respective detection point
of any chemical reaction that has taken place is minimized (Figure 2). It is furthermore
known from the field of liquid chromatography and electrophoresis that separation
of materials can be achieved more rapidly and individual components can be separated
with a higher degree of resolution than has been possible in conventional systems.
Furthermore, microminiaturized laboratory systems enable a considerably reduced consumption
of materials, particularly reagents, and a far more efficient intermixing of the components
of materials.
[0015] Pre-published international patent application WO 98/05424 describes an arrangement
for the handling of a microchip which is already of modular construction. The transport
of materials by means of high electrical voltage represents only one variant of further
conceivable solution concepts. For example, the potential difference required for
transport of materials can also be brought about by application of a pressurized medium,
ideally compressed air on the materials, or another suitable gas medium such as, for
example, inert gas, or by application of negative pressures or vacuum. Furthermore,
materials can be transported by means of application of a suitable temperature profile,
in which context transportation takes place by means of thermal expansion or compression
of the respective material.
[0016] The choice of the respective medium for provision of a potential or of a force for
transport of materials on the microchip will therefore be guided according to the
physical characteristics of the materials themselves, as well as the nature of the
analysis and/or synthesis that is desired to be carried out. In the case of materials
with charged particles, for example charged or ionized molecules or ions, transportation
of materials ideally takes place by means of an electrical or electromagnetic field
of suitable strength, e.g., via electrophoresis. The distance covered by the materials
is dictated by the field strength and (chronological) time duration of the applied
field. In the case of materials free of electrical charge, transportation is ideally
performed by means of a flow medium, for example compressed gas, or applied vacuum,
although electrically driven transport, e.g., electroosmosis, is also optionally employed.
Because of the very small dimensions of the transport conduits on the microchip, for
positive or negative pressure based transport, only relatively low volumes of air,
on the order of magnitude of picoliters, will be required. In the case of materials
with a relatively high coefficient of thermal expansion, a thermal process for the
transportation of materials can be employed, preferably provided that the resultant
temperature increase exerts little or no relevant influence on the reaction kinetics
taking place in the respective test.
[0017] Due to the possible complexity of the reactions being carried out, the number of
necessary contact electrodes may be relatively high, e.g., from about 4, 10, hundreds
or even more. Furthermore, the materials can be moved in transport conduits of any
given spatial configuration. For further control or adjustment of the precise flow
speeds of the materials, in the case of hollow conduits liquid or gel-type buffer
media may be employed that alters the flow speeds through such conduits, e.g., because
of viscosity or increased flow resistance. On the basis of transport of charged molecules
through such a gel, it is possible to adjust flow speeds with particularly high precision
by means of the connected electrical fields. Furthermore, there is the option of providing
the required reagents for the test or even the materials themselves which are to be
examined, predisposed on the microchip.
[0018] Using a buffer gel or a buffer solution, mixtures of charged molecules can advantageously
be transported through the medium by means of an electrical field. For precise separation
of materials and correspondingly precisely timed introduction of the respective materials,
several electrical fields can be simultaneously or consecutively activated, with different
time gradients as appropriate. This also makes it possible to achieve complex field
distributions for fields which migrate over the separation medium. Charged molecules
which migrate with a higher degree of mobility through a gel than other materials
can thus be separated from slower materials of lesser mobility. In this context, the
precise spatial and temporal distribution of fields can be achieved by corresponding
control or computer programs.
[0019] For the above-mentioned microfluidic technology, furthermore, consideration is additionally
being given to the use of micro-mechanical or micro-electromechanical sensor systems,
for example using micro-mechanical valves, motors or pumps. A corresponding survey
of possible future technologies in this environment is given in a relevant article
from Caliper Technologies Corp., which can be downloaded from the Internet at "
www.calipertech.com".
[0020] Presuming the acceptance of this new technology by the relevant circles of users
involved, these microchips will rapidly come into use as commercial products and as
rapid tests in the field of laboratory diagnostics or clinical diagnostics. For that
reason there is a considerable demand for a laboratory arrangement for practical handling
and operation of such a microchip. First, this arrangement simplifies the handling
of chips such that they can also be used in the above-mentioned laboratory environment
by chemistry or biology laboratory technicians having relatively little experience
with the minimal complications. Secondly, a corresponding widespread application of
such microchips and a relatively simple and rapid analysis of measurement results
is made possible. In addition to practical and straightforward ease of handling of
the microchips, the user does not need any more than the minimum of skill in the operation
of the above-mentioned supply systems, particularly with reference to any requirement
for higher voltage or any further technical equipment. Furthermore, a corresponding
test layout also provides detection devices suitable for logging of the measurement
results, such as those which enable automatic detection of the measured data and digitally
outputting these data at the output of the measurement system.
II. Modular Construction of Microchip Laboratory Systems
[0021] In a system according to the invention, the above-mentioned objectives for operation
and for handling of a laboratory microchip, which when used in the microscale analysis
and/or synthesis of fluidic materials is referred to herein as a microfluidic device,
are fulfilled by arrangement of the first supply system within a module unit which
is separably connected with the second physical unit. The described modular layout
thus primarily enables ease of interchangeability of the required means of supply
for provision of the necessary potentials/forces for microfluidic movement of materials
on the microchip, e.g., electrical fields, and thus, overall, ease of adaptability
of the device for various types of the microchip. Thus, the device offers flexible
utilization for various experimental layouts and a corresponding variety of microchips.
[0022] The module unit is preferably designed as an insertable cassette or cartridge. The
installation as a whole can be configured as a permanently installed system or as
a portable system for mobile implementation of an experiment onsite, for example close
by a medical patient. In a preferred embodiment, the proposed module unit includes
the above-mentioned first supply system, e.g., a transport system, in which context
the materials required for the corresponding experiment can also be fed separately
to the microchip. Alternatively, however, materials can also be transported to the
microchip by means of a second supply system and/or unit which is preferably arranged
within the proposed module unit as well.
[0023] It is emphasized that both the first and the second supply systems can contain either
electrical conductors and/or hollow conduits, by means of which the required potential,
and/or the required materials are fed to the microchip whereby the actual sources
of potential or materials are provided by means of a further basic supply unit (see
below). In certain instances, the supply means serve to provide material as well as
the necessary potential to the microfluidic devices(again, see below).
[0024] In case of feeding of materials by means of second supply means, it can further be
envisaged that the first and second supply means commonly exhibit feeding means, preferably
hollow conduits or hollow electrodes, for feeding of the potential or potentials required
for transportation of materials on the microchip, as well as for supply to the microchip
of the materials required for operation of the microchip. These materials may also
be the samples themselves. This makes it possible to achieve a considerable reduction
in the quantity of necessary feed lines for the potential or potentials required for
transfer or for feed of materials, even enabling them to be reduced by a factor of
2, which is particularly significant in the case of microfluidic devices which are
already equipped with a relatively large number of contact electrodes or access ports
for same, and openings for feeding of materials.
[0025] In accordance with a further aspect of the invention, it will be understood that
the module unit which has a separable connection with the second physical unit can
exhibit an integrated supply system for the microchip with an electrical power supply,
compressed gas supply, temperature supply etc. The proposed module unit in this embodiment
thus exhibits all of the supply elements/units required for microchip operation. In
the case of transportation of materials on the microchip by means of electrical forces,
in this context, an electrical power supply, also miniaturized, may be included: one
which can be implemented with known micro-electronic as a high-voltage power supply
within a module unit as proposed. In the case of transportation of materials on the
microchip by means of a gas medium, a corresponding compressed gas supply system is
optionally provided within the module unit. Because of the relatively low volumes
of gas relating to the miniaturized transport conduits on the microchip, it is also
possible to reduce the size of the compressed gas supply, and in particular the gas
reservoir, such that it can be fully integrated into a corresponding module unit.
The same is applicable for a temperature supply system for purposes of thermally induced
transportation of materials.
[0026] In accordance with a further embodiment of the device according to the invention,
the module unit optionally includes an application-related basic supply unit for the
corresponding microchip/microfluidic device. In this embodiment, the module unit comes
ready-equipped with all reagents required for the experiment to be performed and with
the necessary integrated supply system for transportation of materials on the microchip,
so that only the materials to be examined remain to be fed to the microchip.
[0027] In a further advantageous embodiment of the system according to the invention, the
module unit includes an intermediate interface component for bridging supply lines
of the first supply system and corresponding supply lines on the microchip. The advantage
of this increased modular layout is, in particular, that the supply lines of the first
supply means are no longer directly in contact with the corresponding conduits of
the microchip and are thus subject to no dirtying and wear & tear. This is because
only the conduits of the intermediate interface component come into contact with the
corresponding lines or interface elements of the chip. Furthermore, the intermediate
interface component enables straightforward spatial adaptation of the supply lines
to various microchip layouts.
[0028] In particular, the intermediate interface component can be separably mounted on/in
the module unit, and it is preferably mounted on/in the module unit by means of a
bayonet fitting (catch). Alternatively, however, mounting can also be accomplished
by means of conventional mounting devices such as clamps, clips, slots (e.g., standard
commercial mountings or insertion devices for credit cards, particularly chip cards)
etc.
[0029] The information required for detection and analysis of reactions which take place,
e.g., by receiving and recording a detectable signal indicative of the reaction, i.e.,
optical signals, electrochemical signals, etc., furthermore, can be detected by means
of a detection or measurement system which is preferably arranged within the physical
unit in which the microchip is also mounted. This embodiment therefore provides for
additional modularity of the entire layout. For example, the results of a reaction
can be analyzed by means of a laser spectrometer which is arranged in or on the first
physical unit underneath the microchip. Even more advantageously, this analysis unit
can be separably connected with the first physical unit in order to enable the highest
possible degree of flexibility in data analysis, e.g., through interchangeability
of detection systems. Thus, for example, it is possible to provide various laser spectrometers
which perform sensing in different wavelength ranges, or, for example, it is possible
to replace a laser spectrometer with an entirely different type of measurement system.
[0030] In order to achieve further simplification in the handling of the microchip in a
system according to the invention, the first physical unit can further exhibit a mounting
plate for the microchip. The described mounting plate is preferably arranged such
that the microchip can be mounted from above onto this plate and thus the fitting
of the microchip is considerably simplified, despite its relatively small dimensions.
[0031] Finally, as a further stage of modularity of the system according to the invention,
a basic supply unit can be provided which constitutes a third physical unit and which
is connected with the first and with the second physical unit. This physical unit
can, for example, fulfill the function of supplying the entire device/measurement
system with (high) voltage, compressed gas or with the materials and/or reagents required
for the corresponding experimental test.
[0032] The functional components required for a laboratory microchip system of the present
type and its functional operation during a test cycle are illustrated in diagrammatical
form in Figure 1, as briefly described above, with exemplary reference to the microchip
as illustrated in Figure 2. In this drawing, the distinction is made between the material
flow 1 which arises in such a system, i.e. the materials to be examined and the correspondingly
employed reagents, and the information flow 2, firstly in connection with the controlled
transportation of individual materials on the microchip and secondly in connection
with detection of test results.
[0033] Initially, in the area of material flow, the materials to be examined (possibly in
addition to the reagents required for the corresponding test) are fed to the microchip
3. Thereafter, these materials on the microchip are moved or transported, e.g., by
means of electrical forces 4. Both the feed and the movement of materials are brought
about by means of a suitable electronic control 7, as indicated by means of the dotted
line. In this example, the materials are subjected to preliminary treatment 5, before
they undergo the test as such. This preliminary treatment may, for example, consist
of preheating by means of a heating system or pre-cooling by means of a suitable cooling
system in order, for example, to fulfill the required thermal test conditions. As
is known, the temperature conditions for execution of a chemical test usually exert
a considerable influence on the cycle of test kinetics. As is indicated by the arrow,
this preliminary treatment can also take place in a multiple sequence, in which context
there are obviated a pretreatment cycle 5 and a further transport cycle 4'. The above-mentioned
pretreatment can in this instance, in particular, fulfill the function of separation
of materials such as to access only certain specified components of the initial materials
for the corresponding test. Essentially, both the material quantity (quantity) and
the material speed (quality) can be determined by means of the transportation as described.
In particular, precise adjustment of material quantity enables precise metering of
individual materials and material components. Furthermore, the latter processes can
advantageously be controlled by means of electronic control 7.
[0034] After one or more pre-treatments, the actual experimental test/examination takes
place, in which context the test results can be detected on a suitable detection point
of the microchip 6. Detection advantageously takes place by means of optical detection,
e.g. a laser diode in conjunction with a photoelectric cell, a mass spectrometer,
which may be connected, or by means of electrical detection. The resultant optical
measurement signals are then fed to a signal-processing system 8, and thereafter to
an analysis unit (e.g. suitable microprocessor) for interpretation 9 of the measurement
results.
[0035] Following the above-mentioned detection 6, there is the option of implementation,
as indicated by the dotted line, of further test series or analyses or separation
of materials, e.g., those in connection with various test stages of a chemical test
cycle which is, overall, more complicated. For this purpose, materials are transported
onwards on the microchip after the first detection point 6, and to a further detection
point 6'. There, the procedure theoretically defined according to stages 4' and 6
is performed. Finally, the materials are fed, after termination of all reactions/tests,
to a material drain (not illustrated here) by means of a concluding transport cycle
or collection cycle 4"'.
[0036] Figure 2, as noted above, illustrates a typical laboratory microchip which is suitable
for utilization in a system according to the invention. Initially, the technical setup
of such a microchip is extensively described, because this has an important part to
play in determining the structure of the system according to the invention, which
will be described therein below. On the upper side of an illustrated substrate 20,
microfluidic structures are provided, through which materials are transported. Substrate
20 may, for example, be made up of glass or silicon, in which context the structures
may be produced by means of a chemical etching process or a laser etching process.
Alternatively, such substrates may include polymeric materials and be fabricated using
known processes such as injection molding, embossing, and laser ablation techniques.
Typically, such substrates are overlaid with additional substrates in order to seal
the conduits as enclosed channels or conduits.
[0037] For sampling of the material to be examined (hereafter called the "sample material")
onto the microchip, one or several recesses 21 are provided on the microchip, to function
as reservoirs for the sample material. In performing a particular exemplary analysis
or test, the sample material is initially transported along a transport duct or channel
25 on the microchip. In this example, transport channel 25 is illustrated as a V-shaped
groove for convenience of illustration. However, the channels of these microfluidic
substrates typically comprise sealed rectangular (or substantially rectangular) or
circular-section conduits or channels.
[0038] The reagents required for the test cycle are typically accommodated in recesses 22,
which also fulfill the function of reagent and/or sample material reservoirs. In this
example, two different materials could readily be manipulated. By means of corresponding
transport conduits 26, these are initially fed to a junction point 27, where they
intermix and, after any chemical analysis or synthesis has been completed, constitute
the product ready to use. At a further junction 28, this reagent meets the material
sample to be examined, in which the two materials will also inter-mix.
[0039] The material formed, then passes through a conduit section 29, which, as shown has
a meandering geometry which functions to achieve artificial extension of the distance
available for reaction between the material specimen and the reagent. In a further
recess 23 configured as a material reservoir, in this example, there is contained
a further reagent which is fed to the already available material mix at a further
junction point 31.
[0040] The reaction of interest takes place after the above-mentioned junction point 31,
which reaction can then be detected, ideally by contactless means, e.g., optically,
within an area 32 (or measurement zone) of the transport duct by means of a detector
which is not illustrated here. In this context, the corresponding detector can be
located above or below area 32). After the material has passed through the above-mentioned
area 32, it is fed to a further recess 24, which represents a waste reservoir or material
drain for the waste materials which have been produced, overall, in the course of
the reaction.
[0041] Finally, on the microchip there are provided recesses 33 which act as contactless
surfaces for application of electrodes and which in turn enable the electrical voltages,
and even high voltages, required for connection to the microchip for operation of
the chip. Alternatively, the contacting for the chips can also take place by means
of insertion of a corresponding electrode point directly into the recesses 21, 22,
23 and 24 provided as material reservoirs. By means of a suitable arrangement of electrodes
33 along transport conduits 25, 26, 29 and 30 and a corresponding chronological or
intensity-related harmonization of the applied fields, it is then possible to achieve
a situation in which the transportation of individual materials takes place according
to a precisely dictated time/quantity profile, such that it is possible to achieve
very precise consideration of and adherence to the kinetics for the underlying reaction
process.
[0042] In pressure driven transport of materials within the microfluidic structure, it is
typically necessary to make recesses 33 such that corresponding pressure supply conduits
closely and sealably engage them so as to make it possible to introduce a pressurized
medium, for example an inert gas, into the transport conduits, or apply an appropriate
negative pressure.
[0043] The general setup of a system according to the invention is now described by the
block diagram depicted in Figure 3. Here, the individual components of the entire
system 40 are constructed on a strictly modular basis such as to achieve the maximum
possible flexibility in operation of the system. The microchip 41 is accommodated
in a first physical unit 42 and is preferably arranged on a mounting plate (illustrated
in Figures 4 and 5d), such that the microchip 41 has ease of access from the top and
its installation and removal is greatly simplified as the result. Furthermore, as
a further section of the first physical unit 42, a mounting 43 is provided for an
optical device 43' for contactless detection of the results of the tests performed
on microchip 41, particularly the chemical reactions that take place there. Preferably,
the optical measurement device 43' constitutes a laser spectrometer; however, other
forms of measurement system, such as, for example, a mass spectrometer or infrared
sensor system, may be used.
[0044] The supply systems that provide the forces necessary for transportation of materials
on the microchip are accommodated in a second physical unit 44, which is spatially
separate from the first physical unit 42. Preferably, the supply systems are arranged
in an insert or in a cartridge 44' or integrated in the same, with a separable connection
to the second physical unit 44. It is possible to consider supply systems, in the
context of transportation of materials by means of electrical forces, relating to
a power supply and electrical contracts which bring about a conductive connection
with the opposite electrodes 33 of the appropriate form as described in Figure 2,
as soon as the first and second modules are brought together. Within a third physical
unit 45, further installations, e.g. a basic power supply or electronic analyzer for
processing of the signals/data supplied by measurement installation 43, can be provided.
Further, the data output from the measurement device 43 or from the electronic analyzer
which is integrated into the third physical unit 45, are optionally accessible from
outside via an analogue or digital data-processing interface 46.
[0045] A further exemplary embodiment of the invention is now described on the basis of
the illustration shown in Figure 4 which shows a portion of the components already
illustrated in Figure 3. By analogy with the embodiment illustrated in Figure 3, a
first physical unit 50 is provided which comprises a mounting plate 51 for supporting
a microchip 52. In this example, the microchip 52 comprises two different types of
connecting components. The first type are recesses 53 which provide access for electrical
contacts for provision of the voltages required for transportation of materials on
the microchip. These recesses 53 can either fulfill the function of purely mechanical
access points for electrodes, or they themselves can represent electrodes, for example
by means of suitable metal-coating of the inner surface of the recesses. Furthermore,
such metal-coated recesses can have an electrically-conductive connection with further
electrode surfaces arranged on the microchip, in order to deliver the electrical fields
used for transportation of materials. Such electrode surfaces can also be made by
known coating technologies.
[0046] As a second type of connecting components on the microchip, recesses 54 can be provided
for holding/deposit of materials, i.e., reagents. Again, in accordance with the specification
form illustrated in Figure 4, there is provided a second physical unit 55 which contains
the necessary supply systems 56 for operation of the microchip 52. Preferably, the
supply systems 56 constitute a micro-system which, by means of suitable miniaturization
of the necessary components, also supplies the necessary electrical power for the
necessary gas pressure via corresponding electrodes 58 (or lines/conduits 58 in the
case of a pressure supply system) and also in the form of a cartridge which is inserted
into module 55. In the case of electrical supply to the microchip, miniaturization
of the electrical voltage supplies and circuitry can be achieved by conventional integrated
technology. Similarly, in the case of supplying pressure to the channels of a microchip,
such supply can be accomplished using corresponding technologies already known from
the field of laboratory technology or micro-mechanics. In this context, it is also
possible to integrate supply containers for the compressed-gas medium since, as already
mentioned, the volumes of gas required relate only to the order of magnitude of picoliters.
[0047] In this embodiment, furthermore, the second physical unit 55 comprises an intermediate
interface component 57 which has a separable connection with the supply system 56,
functioning as a replaceable interface array, as shown. The intermediate interface
component provides an electrical connection 60 (or connecting conduits), by means
of which electrodes 58 (or conduits) of supply system 56 and the correspondingly allocated
opposite electrodes 53 of the microchip can be bridged. Accordingly, connecting lines
61 can be used for bridging conduits for supplying fluids or other materials. In this
case, sealing elements (not illustrated here) are necessary between lines 59 and 61.
On the one hand, the above-mentioned bridging fulfills the function of avoiding the
wear & tear or dirtying of the electrodes (or conduits) of supply system 56 that could
inevitably arise upon contacting with the microchip, by having the intermediate component
or carrier made (which would be subjected to dirtying and wear & tear) in the form
of a "disposable product". Furthermore, as illustrated in this embodiment, the intermediate
component or carrier can also fulfill the function of providing spatial adaptation
of the electrodes of supply system 56 to the corresponding surface or spatial arrangement
of the microchip electrode surfaces. This provides for an advantageous facility of
achieving adaptation of the entire measurement/operating installation to a special
microchip layout purely by replacement of cartridge 56 and/or intermediate interface
component 57. In particular, cartridge replacement enables simple and rapid adaptation
of the handling installation to various test types or various modes of operation,
such as, for example, interchange between electrical supply and compressed-gas supply
to the microchip, or for electrical supply to microchips having different interface
layouts, e.g., reservoir patterns.
[0048] A preferred embodiment of the invention, in which the module unit according to the
invention is made as a replaceable cartridge, is illustrated by figures 5a-5d. In
particular, there is illustrated a sequence of images on the basis of which a typical
operating cycle of the proposed system is shown. In these Figures, similar components
are identified using common reference numerals. Figure 5a illustrates a cartridge
70, which is integrated in a supply system (not illustrated here in closer detail)
for a microchip. The supply lines (conduits) of the supply system are fed to outside
by means of an appropriate contact electrode array71, in which context this electrode
array is designed in the specification example shown here as an interchangeable contact
plate 71, which may, for example, be made of ceramics or polymeric materials, e.g.,
Teflon, or polyimide. Using an internal basic supply system for the entire handling
system (also not illustrated here), the cartridge is connected via plug-in connections
72 which interact with corresponding opposite components envisaged in the second module,
in the normal way, and which activate the corresponding contact connections when the
cartridge is plugged into the module.
[0049] Accordingly, the contacting of the contact electrodes of the supply system with the
corresponding contacts on the microchip is performed by means of an intermediate interface
component, shown as interface component 73, which, in the example shown here, bridges
the contact electrodes without changing their spatial arrangement in relation to the
microchip. The main advantages of this intermediate interface component 73 have already
been described. The intermediate interface component has a separable connection to
the cartridge by means of a bayonet connector 74, 75. For that reason, on cartridge
70 a corresponding bayonet thread 75 is provided to engage bayonet 74. Bayonet connection
74, 75 enables rapid, straightforward replacement of intermediate interface component
73, which can thus be used in the capacity of a spare part or disposable product,
and can, for example, be interchanged and/or cleaned between each test cycle.
[0050] Figures 5b and 5c illustrate individual assembly stages for fitting of intermediate
interface component 73 into a cartridge 70. In accordance with Figure 5b, intermediate
interface component 73 is initially inserted into cartridge 70 in the position envisaged
for assembly, and then - as illustrated in Figure 5c - mounted by means of bayonet
connection 74, 75 on or within cartridge 70. In this context, a circular section 76
made in bayonet 74 engages in corresponding bayonet thread part 75. Figures 5 b and
c illustrate a further advantage of the cartridge proposed under the invention (module
unit), i.e. that intermediate interface component 73 can, after removal of cartridge
70 from the second physical unit, be readily fitted back into cartridge 70.
[0051] Finally, Figure 5d illustrates how a correspondingly pre-assembled cartridge can
be fitted into an equipment (instrument) housing 77 which contains all of the modules.
In the specification example, which is illustrated, cartridge 70 is inserted into
a slot provided in the second physical unit 78. However, other means of mounting are
also conceivable, for example a snap connection or magnetic connection. By folding-down
of second physical unit 78, it is brought into contact with the first physical unit
79, which fulfils the function of a previously installed microchip which is illustrated
here, and thus the necessary contact connections are automatically made for operation
of the microchip. In this example, the microchip is integrated into a chip casing
or chip mounting 84 which provides access apertures 85 to the corresponding contacts
or insertion apertures provided on the microchip which is arranged below these apertures.
The illustrated arrangement of the microchip in a chip casing 84 provides further
simplification of handling, and in particular with regard to fitting of the microchip
and thus, overall, operation of the invention's proposed system.
[0052] Figure 6a and 6b depict a diagram of an embodiment of a casing 77 corresponding to
Figure 5d, in which the two physical units 78, 79 according to the invention are interconnected
by means of a swivel joint (hinge connection) 80. In this context, the swivel joint
is advantageously arranged in spatial terms such that the contact pins 83 provided
in the supply system 81 do not become offset by the recesses provided in the microchip
82 when it is inserted into them, which in the worst case would lead to unwanted damage
to contact pins 83 or even damage to the microchip 82.
[0053] All publications and patent applications are herein incorporated by reference to
the same extent as if each individual publication or patent application was specifically
and individually indicated to be incorporated by reference. Although the present invention
has been described in some detail by way of illustration and example for purposes
of clarity and understanding, it will be apparent that certain changes and modifications
may be practiced within the scope of the appended claims.
1. A device for operating a microchip with a microfluid structure for chemical, physical,
and/or biological processing, the microchip including supply elements corresponding
with the microfluid structure, comprising
a supply unit for providing a potential for moving substances corresponding to
the microfluid structure, the supply unit having supply lines for enabling the potential
to be coupled to the microchip, the supply lines being arranged to interact with the
supply elements which correspond to the microfluid structure,
an interface element, and
a holder for carrying the interface element,
the interface element including a structure for connecting the supply lines with
at least one of the supply elements that correspond to the microfluid structure,
the interface element and the holder having structures for enabling the interface
element to be releasably connectable to the holder so that the interface element can
be selectively secured to and removed from the holder,
the interface element having exterior surfaces resistant to the substances processed
by the microchip.
2. The device according to claim 1, wherein the interface element has electrodes for
supplying the microchip with electrical energy for generating a potential required
for the microfluid movement of the substances on the microchip.
3. The device according to claim 1, wherein the interface element has channels for supplying
the microchip with mechanical energy for generating a potential required for the microfluid
movement of the substances on the microchip.
4. The device according to claim 1, wherein the interface element has channels for supplying
the microchip with thermal energy for generating a potential required for the microfluid
movement of the substances on the microchip.
5. The device according to claim 2, wherein the channels are arranged for supplying the
microchip with mechanical energy for feeding a pressurized fluid.
6. The device according to claim 1, wherein the device is arranged for analyzing or synthesizing
substances supplying the microchip with at least some of the necessary substances
for processing or analysis, wherein the interface element has channels for supplying
the microchip with these substances.
7. The device according to claim 6, further including seals at the ends of the channels
of the interface element for preventing the substances from exiting.
8. The device according to claim 1, wherein the interface element includes an electrically
insulating substrate in which the electrodes and channels are embedded.
9. The device according to claim 8, wherein the substrate is a ceramic.
10. The device according to claim 8, wherein the substrate is a polymer.
11. The device according to claim 1, wherein the interface element and the supply unit
are arranged and constructed so the interface is releasably attached to the supply
unit.
12. The device according to claim 11, wherein the interface element includes a bayonet
lock for releasably attaching the interface unit to the supply unit.
13. The device according to claim 1, wherein the interface element and the supply unit
respectively include a first coding element for identifying the interface element,
a second coding element on at least one of the supply units and the microchip, the
first and second coding elements corresponding with each other and interacting with
each other.
14. The device according to claim 1, wherein the microchip is in a first assembly, and
the supply unit as well as the interface element are in a module, a second assembly,
the module and second assembly being arranged and constructed so the module is releasably
connected to the second assembly.
15. The device accordingly to claim 14, further including a magnet/Hall sensor pair, the
second assembly including elements mounted on the module, and an output device responsive
to a Hall sensor of the magnet/Hall sensor pair.
16. The device according to claim 15, wherein the output device includes a shut-off for
the device for operating the laboratory microchip.
17. The device according to claim 15, wherein the output device includes a warning device.
18. The device according to claim 1 wherein the cooperating structures are such that the
interface element is locked in place on a securing structure of the holder in response
to rotation of the interface element relative to the holder.
19. The device according to claim 1 further including a housing for the (1) microchip,
(b) holder, (c) interface element and (d) supply unit, and wherein the holder and
housing having cooperating structures for enabling the holder to be selectively (a)
locked into place in the housing and (b) released and removed from the housing.
20. A device for operating a microchip with a microfluid structure for chemical, physical,
and/or biological processing, the microchip including supply elements corresponding
with the microfluid structure, comprising
a supply unit for providing a potential for moving substances corresponding to
the microfluid structure, the supply unit having supply line for enabling the potential
to be coupled to the microchip, the supply lines being arranged to interact with the
supply elements which correspond to the microfluid structure,
an interface element, and
a holder for carrying the interface element,
the interface element including a structure for connecting the supply lines with
at least one of the supply elements that correspond to the microfluid structure,
the interface element and the holding having structures for enabling the interface
element to be releasably connectable to the holder so that the interface element can
be selectively secured to and removed from the holder,
the interface element consisting of materials and structures that can be cleaned
with chemicals for reuse.
21. The device according to claim 20 further including a housing for the (a) microchip,
(b) holder, (c) interface element and (d) supply unit, and wherein the holder and
housing having cooperating structures for enabling the holder to be selectively (a)
locked into place in the housing and (b) released and removed from the housing.
22. A device for operating a microchip with a microfluid structure for chemical, physical,
and/or biological processing, the microchip including supply elements corresponding
with the microfluid structure, comprising
a supply unit for providing a potential for moving substances corresponding to
the microfluid structure, the supply unit having supply lines for enabling the potential
to be coupled to the microchip, the supply lines being arranged to interact with the
supply elements which correspond to the microfluid structure,
an interface element, and
a holder for carrying the interface element,
the interface element including a structure for connecting the supply lines with
at least one of the supply elements that correspond to the microfluid structure,
the interface element and the holder having structures for enabling the interface
element to be releasably connectable to the holder so that the interface element can
be selectively secured to and removed from the holder,
a housing for the (a) microchip, (b) holder, (c) interface element and (d) supply
unit, the holder and housing having cooperating structures for enabling the holder
to be selectively (a) locked into place in the housing and (b) released and removed
from the housing.
23. A system for enabling plural microchips with different microfluidic configurations
to be interchangeably used, the different microfluidic configurations having different
supply element configurations, comprising a supply unit for providing a potential
for moving substances in a microchip being used in a device of the system, the supply
unit having supply lines for enabling the potential to be coupled to the microchip
being used in the device, a plurality of interface elements having supply lines for
selective connection between the supply lines of the source and the supply elements
of the microchips, different ones of the interface elements having different supply
line configurations for supplying potentials from the supply lines of the source to
the supply elements of the microchips with the different microfluidic configurations,
the interface elements having exterior surfaces that are resistant to the substances
processed by the microchip.
24. A system for enabling plural microchips with different microfluidic configurations
to the interchangeably used, the different microfluidic configurations having different
supply element configurations, comprising a supply unit for providing a potential
for moving substances in a microchip being used in a device of the system, the supply
unit having supply lines for enabling the potential to be coupled to the microchip
being used in the device, a plurality of interface elements having supply lines for
selective connection between the supply lines of the source and the supply elements
of the microchips, different ones of the interface elements having different supply
line configurations for supplying potentials from the supply lines of the source to
the supply elements of the microchips with the different microfluidic configurations,
the interface elements consisting of materials and structures that can be cleaned
with chemicals for reuse.
25. A system for enabling plural microchips with different microfluidic configurations
to the interchangeably used, the different microfluidic configurations having different
supply element configurations, comprising a supply unit for providing a potential
for moving substances in a microchip being used in a device of the system, the supply
unit having supply lines for enabling the potential to be coupled to the microchip
being used in the device, a plurality of interface elements having supply lines for
selective connection between the supply lines of the source and the supply elements
of the microchips, different ones of the interface elements having different supply
line configurations for supplying potentials from the supply lines of the source to
the supply elements of the microchips with the different microfluidic configurations,
the interface elements including a structure for connecting the supply lines with
at least one of the supply elements that correspond to the microfluid structure, the
interface element and the holding having structures for enabling the interface unit
to be releasably connectable to the holder so that the interface element can be selectively
secured to and removed from the holder, a housing for the (a) microchip, (b) holder,
(c) interface element and (d) supply unit, the holder and housing having cooperating
structures for enabling the holder to be selectively (a) locked into place in the
housing and (b) released and removed from the housing.