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EP 0 894 532 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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22.09.2004 Bulletin 2004/39 |
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Date of filing: 30.07.1998 |
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International Patent Classification (IPC)7: B01L 3/00 // G01N33/48 |
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Method and apparatus for the extraction and handling of biological liquids from thin
walled receptacles
Vorrichtung und Verfahren zur Extraktion bzw. Handhabung von biologischen Flüssigkeiten
in dünnwändigen Behältern
Méthode et dispositif pour l'extraction et la manipulation de liquides biologiques
contenus dans des récipients à parois minces
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Designated Contracting States: |
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AT BE CH DE ES FR GB IT LI NL PT |
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Priority: |
01.08.1997 ES 9701710
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Date of publication of application: |
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03.02.1999 Bulletin 1999/05 |
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Proprietor: Probitas Pharma, S.A. |
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08005 Barcelona (ES) |
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Inventor: |
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- Martinell Gisper-Sauch, Enrique
08010 Barcelona (ES)
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Representative: Duran Moya, Luis-Alfonso et al |
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DURAN-CORRETJER
Còrsega, 329
(Paseo de Gracia/Diagonal) 08037 Barcelona 08037 Barcelona (ES) |
| (56) |
References cited: :
EP-A- 0 350 792 US-A- 4 790 842
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US-A- 4 399 103 US-A- 4 846 005
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| Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
|
[0001] The present invention refers to a method and apparatus for handling and extracting
biological samples held in receptacles with thin walls such as those obtained by sectioning
a tubular element with a number of pockets for the purpose of holding the samples
to be analyzed.
[0002] The present invention offers important characteristics of novelty and inventive activity
in relation to the state of the art, enabling biological liquids to be handled in
a manner which offers considerable security against external contamination and avoids
the possibility of leakage from the sample.
[0003] The invention is especially applicable to the treatment of blood products, such as
whole blood, red cells, serum etc. and facilitates the carrying out of analysis thereof.
[0004] At the present time blood, red cells, serum, etc. from a sample taken from a donor
which is intended, for example, for transfusion are usually stored in PVC pockets
together with an anti-coagulant and are duly labelled. The contents of the pockets
must be analyzed on numerous occasions, at least for each patient who may be given
a transfusion, and in these processes it is highly important to prevent accidental
contamination (both contamination of the exterior by the contents of the pocket and
contamination of the contents from the exterior) and also to prevent confusion occurring
in the identification of the samples.
[0005] Normally each pocket is provided with a long PVC tube which is filled with liquid
from the pocket after extraction and is immediately sealed at several points and at
its end by welding the walls of the tube by the high frequency method (or any other
method). Thus several segments are formed which contain samples of the liquid and
these are stored without being cut or separated from the pocket. The tube and the
pocket can be marked (for example with numbers or bar codes) a number of times so
that each segment contains at least one distinguishing mark. If high frequency welding
is used, the electrodes can leave a notch in the welded joint so that subsequently
the segments can be separated from one another by traction leaving both ends completely
closed and avoiding any leakage of liquid. This whole process is safe and free of
contamination.
[0006] When the contents of a pocket have to be tested, the last of the segments is separated
and the test is carried out on the liquid contained therein. For this purpose a test
tube is usually taken and placed on a tube rack, and the segment is cut by means of
scissors and is emptied by way of the tube, then the empty segment is thrown away
and the test is carried out on the tube, which has previously been marked with the
same number as that which identifies the pocket.
[0007] In these conditions:
- the sample has ceased to be separately identified upon becoming separated from the
segment,
- upon cutting the segment, a stump or end piece is detached and this must be thrown
away,
- the scissors becomes soiled and must be cleaned for the next sample,
- upon pouring the liquid into the tube splashing may occur, and
- there is a risk of contamination of the sample from the exterior, and also from the
sample outwards and between samples, and danger to humans of viral or bacterial contamination
(by AIDS, HEPATITIS, etc.)
[0008] The same or similar problems are found with other procedures used to recover liquid
from inside the segments.
[0009] One is therefore drawn to the conclusion that although the creation of a number of
aliquot parts from the donated sample by means of segments is a clean and safe system,
further use of the said segments is very unsatisfactory due to the fact that it does
not afford a high standard of hygiene and is potentially dangerous. US-A-4 846 005
and EP-A-0 350 792 disclose devices for blood gathering and testing.
[0010] The present invention seeks to overcome the problems described above, by providing
a method as defined in claim 1 and an apparatus as defined in claim 2 for extracting
and handling blood samples held in container elements with thin walls, enabling the
said operations to be carried out safely and aseptically, without any real possibility
of actual contact with the analysis personnel and enabling the samples to be identified
easily during the whole cycle of tests.
[0011] In order to achieve its aims, the present invention provides apparatus comprising
an intermediate receptacle to receive the tubular element holding the sample of biological
liquid, the said receptacle being constructed in a manner which is generally similar
to that of a test tube, in order to make it possible for the sample to be handled
in a manner similar to that which would be used in the case of a test tube, the said
intermediate receptacle internally comprising buffering and centring means for the
purpose of receiving the tubular receptacle with thin walls for holding the sample
of biological liquid, thus creating a lower small container for collecting the biological
liquid which will be released from the tubular element which holds it by any suitable
means. The size of the intermediate receptacle must be such that, in relation to the
tubular element containing the biological sample it enables pipetting to be carried
out, possibly by an automatic device of the said intermediate receptacle.
[0012] The method for handling the biological liquid samples will therefore basically comprise
the following successive stages:
[0013] Placing a tubular container element, one constructed with thin walls, containing
the biological sample inside the intermediate receptacle and engaging it with means
for centring and retaining the same.
[0014] Perforating and cutting or tearing the side wall of the tubular element holding the
biological sample at a minimum of one point, preferably close to the lower floor of
the said circular element, and optionally, making one or more further perforations
in the upper part of the same in order to facilitate an intake of air.
[0015] Squeezing the tubular element holding the biological sample in order to cause the
whole of the said sample to be discharged towards the inside of the intermediate receptacle,
or emptying by gravity in the case where an upper intake of air is provided for.
[0016] Pipetting the sample in order for the same to be subjected to the required analysis.
[0017] Temporary storage of the device holding the tubular element, which is provided with
legible marks for the purpose of identifying the sample.
[0018] The device for carrying out this procedure should preferably be manufactured from
a low cost plastic material, which is provided internally with means for centring
and holding the tubular element holding the biological sample and a small container
for collecting the biological liquid after the said tubular element has been ruptured
and squeezed, means being provided for rupturing the tubular element and for squeezing
out its contents. In a preferred embodiment of this method, the intermediate receptacle
will be produced from two parts or sections, one of which comprises the centring and
holding means for the tubular element which holds the biological sample and likewise,
means such as projections, blades or other suitable components for the purpose of
making cuts in the tubular element containing the biological sample. In this embodiment
one section will preferably be connected to the other, either by being moulded in
one piece or by being constructed with external hinges which may be situated in the
lower portion of a cover extending lengthwise or laterally.
[0019] In all cases it must be possible to carry out the method which is the subject of
the invention in a convenient and rapid manner and in conditions which are especially
aseptic.
[0020] In order to facilitate understanding of the invention, various drawings are annexed
hereto by way of explanatory but non-restrictive example, showing embodiments of the
present invention.
[0021] Figures 1 and 2 are both views in cross-section, shown diagrammatically, of one form
of device according to the present invention.
[0022] Figure 3 shows a view from above of a device according to the present invention,
which makes it possible to appreciate the internal visibility of the tubular element,
due to the fact that it is transparent.
[0023] Figure 4 shows a diagrammatic cross-section of the device itself.
[0024] Figures 5 and 6 are views in perspective of a device according to the present invention,
showing the components in an open position and in a closed position, respectively.
[0025] Figure 7 shows a cross-section of a device according to the present invention showing
the positioning of a pipetting needle.
[0026] According to this invention, in order to handle and extract liquids from receptacles
with thin walls, a cut will be made in one of the said receptacles indicated with
the numeral 1 in Figure 1, this being the usual tubular unit containing various individual
containers of the same sample; in order to carry out various tests, the said unit
is placed centrally inside a special device which basically comprises a section 2
for the purpose of holding the tubular element, a section 3 which can be connected
to section 2 and which is designed to compress and rupture at various points of receptacle
1, and a section 4 in the lower portion of which a small container is arranged, this
said lower portion being preferably common to sections 2 and 3 and preferably designed
to catch the sample of liquid to be analyzed. At least one of the said sections or
components 2 and 3 will be constructed from a transparent material, in order to make
it possible to read from outside the identification marks of the sample which refer
to the receptacle containing the sample.
[0027] After the receptacle 1 with thin walls has been placed in position and centred, this
receptacle being preferably constructed from a thin plastic material, the said receptacle
will be held in position by means of an abutment 5 which may have various forms, and
will be subjected to the action of section 3 of the device, which will in the first
place produce transverse compression of the receptacle 1 and will also rupture the
walls of the receptacle by contact at several points, one point being preferably situated
close to the lower end and another point or points being situated close to the upper
portion, in order to permit an intake of air to permit complete emptying of the tube;
this will contribute to the compression effect of section 3 upon section 2, thereby
squeezing the tube, the contents of which will be conveyed into the lower small container
4 in the form of a liquid mass 6, which will then be available to receive reagents,
the said small container being capable of being partially removed it necessary, and
also capable of being further handled, all of these operations being carried out by
means of a pipetting system as shown diagrammatically in Figure 7 by means of the
pipetting needle 7. Alternatively, it is possible to empty the tube by means of a
single lower perforation, which is made in such a manner as to prevent any intake
of air, and squeezing the tube.
[0028] Preferably, sections 2 and 3 of the device will be hinged to each other at the lower
section 4. However, the main characteristic of the device is that the two sections
2 and 3 can be moved in relation to one another, in order to clamp and compress the
inner tubular receptacle or container 1, whereby the arrangement of both sections
can be variable; for example, they can be movable rectilinearly, in form of laterally
hinged container and cover parts, or arranged in any other manner which achieves the
required aims, i.e., that the receptacle with thin walls carrying the sample for analysis
is well centred, that the liquid contained in the said tubular receptacle is collected,
and also that once the integral components of the device have been adapted so as to
ensure that the receptacle is ruptured and squeezed, the unit which is constructed
in this manner offers fluid-tight conditions which are similar to those of a test
tube, and which makes it possible for the device to be used in the later analytical
stages.
[0029] In order to achieve the desired objects, the device which is the subject of the present
invention will comprise an internal passage 8 which will be substantially concentric
with the liquid mass 6 in the lower small container 4, so as to enable the pipetting
needle 7 to be inserted, and similarly the device will be provided with means for
cutting the tubular element, the said means being constructed in the form of sharp
points or projecting points of another type, knife components, etc. which are shown
diagrammatically in the drawings and indicated by the numerals 9, 10 and 11. One of
these components will cut into the tubular component near the lower end, which is
designed as an outlet for the contents of the receptacle, while the other means, if
they are provided, will be situated in the higher portion of the receptacle for the
purpose of enabling air to be taken inside the said receptacle, in order to assist
the process of emptying the same. In the case shown in Figures 1 and 2 the component
2 is provided with projecting points 9, 10 and 11 and the element or section 3 has
corresponding recesses 12, 13 and 14 in order to permit the cutting components to
be partially inserted into the tubular component 1 for the purpose of rupturing its
walls.
[0030] For the purpose of holding the two components or sections 2 and 3 of the device once
the rupturing and squeezing actions have been carried out, it will be possible to
provide side flaps 15 or other similar components in one of the sections, the said
flaps being designed so that they can be inserted into one another as shown by numeral
16 in Figure 5, and the same effect can similarly be obtained with other fastening
components ensuring that the two components are well secured to each other.
[0031] Obviously, it will also be possible for the desired effect to be obtained by hinging
the two sections 2 and 3 by means of an appropriate pivot 17 as shown in Figures 5
and 6.
[0032] Thus, the described method will comprise a first stage of centring and axially holding
the tubular element inside the rupturing and squeezing device, subsequently simultaneously
rupturing transversely at a point close to the lower end of the tubular element and
optionally at points which are situated in the extreme upper portion of the same and
finally compressing the receptacle in order to squeeze out the liquid held inside
the same, the empty tubular receptacle becoming lodged inside the device, the said
device being manufactured from transparent materials in order to enable the used receptacle
to act as a holder for the marks identifying the sample, thus enabling the sample
to be identified both visually and automatically in an automated analytical apparatus.
1. A method for extracting and handling biological liquids from thin-walled tubular receptacles
in which they are held, and handling the same, wherein a thin-walled tubular element
is used for holding a sample of liquid, which tubular element is provided externally
with identifying marks and is inserted inside a device having transparent walls, so
that it is centred laterally and axially, which device is made to carry out the controlled
rupturing of the receptacle at a point which is close to its lower end in order to
empty the receptacle, and optionally at points which are close to its top end so as
to provide for air intake, then transversely compressing the tubular element so as
to squeeze the same, the tubular element being lodged securely in the rupturing and
squeezing device so as to ensure that the identifying data of the sample contained
in the said thin-walled receptacle can still be read.
2. Apparatus for extracting and handling biological liquids from thin-walled tubular
receptacles (1) in which they are held and handling the same, by the method according
to claim 1, wherein said apparatus comprises at least two sections (2, 3) which can
be joined to each other, one section being movable in relation to another, and including
means for radially and axially holding the thin-walled tubular receptacle containing
a sample of liquid and being provided with means whereby the two sections of the apparatus
co-operate to cause the thin-walled receptacle to be ruptured at desired points, the
said sections being constructed so that the thin-walled receptacle can be squeezed
after the said receptacle has been ruptured, and the section (2) which directly receives
the thin-walled receptacle having transparent characteristics, in order to facilitate
reading from outside of identifying marks which identify the said receptacle which
holds the sample to be analyzed.
3. Apparatus according to claim 2, characterised in that both sections of the same are connected to a container-section (4) with liquid-tight
properties so that it can receive the liquid to be analyzed which is held in the thin-walled
receptacle.
4. Apparatus according to claims 2 and 3, characterised in that the two connecting sections of the device and the container-section for receiving
the same constitute a unit made of plastics material, whereby the two main sections
of the device are hinged to each other and to the said container-section.
5. Apparatus according to claims 2 and 3, characterised in that the said two sections are hinged to each other and one of them is integral with the
container-section for receiving the liquid to be analyzed.
6. Apparatus according to claims 2 to 5, characterised in that one of the two sections holds an axial conduit (8) affording access for a pipetting
needle, which can be inserted so as to extend into the container-section.
7. Apparatus according to claims 2 to 5, characterised in that one of the said sections is provided with cutting elements (9, 10, 11) which are
capable of cutting or perforating the receptacle holding the sample to be analyzed,
at the required points.
8. Apparatus according to claim 7, characterised in that one section of the device is provided with recesses (13, 14) which co-operate with
the cutting elements of the other section, for the purpose of compressing and cutting
the receptacle holding the liquid to be analysed.
9. Apparatus according to claims 2 to 8, characterised in that holding means (15, 16) are provided between the two integral sections of the device
to enable them to be secured in position after they have been interengaged with one
another.
10. Apparatus according to claims 2 to 9, characterised in that the two integral sections and the said container-section can be interengaged to form
a unit, the overall form of which is similar to that of a test tube.
1. Verfahren zum Extrahieren und Handhaben biologischer Flüssigkeiten aus dünnwandigen
röhrenförmigen Behältern, in welchen diese enthalten sind, und zum Handhaben derselben,
bei dem ein dünnwandiges röhrenförmiges Element zum Halten einer Flüssigkeitsprobe
verwendet wird, wobei das röhrenförmige Element äußerlich mit identifizierenden Markierungen
versehen und in ein Gerät mit transparenten Wänden eingeführt ist, so dass es lateral
und axial zentriert ist, und wobei das Gerät zum Ausführen eines kontrollierten Auseinanderbrechens
des Behälters an einem Punkt ausgelegt ist, welcher nahe seinem unteren Ende liegt,
um den Behälter zu leeren, und wahlweise an Punkten, welche nahe an seinem oberen
Ende liegen, um einen Lufteinlass bereitzustellen, ferner das röhrenförmige Element
transversal komprimiert wird, um dieses zusammenzudrücken, und wobei das röhrenförmige
Element fest in dem zerbrechenden und zusammendrückenden Gerät untergebracht ist,
so dass sichergestellt wird, dass die identifizierenden Daten der in den dünnwandigen
Behälter enthaltenen Probe weiterhin gelesen werden können.
2. Verfahren zum Extrahieren und Handhaben biologischer Flüssigkeiten aus dünnwandigen
röhrenförmigen Behältern (1), in welchen diese enthalten sind, und zum Handhaben derselben
durch das Verfahren nach Anspruch 1, bei dem die Vorrichtung wenigstens zwei Abschnitte
(2, 3) umfasst, welche miteinander verbunden werden können, wobei ein Abschnitt im
Verhältnis zu dem anderen bewegbar ist, und Mittel zum radialen und axialen Halten
des dünnwandigen röhrenförmigen Behälters umfasst, der eine Flüssigkeitsprobe enthält,
und mit Mitteln versehen ist, mit denen die zwei Abschnitte der Vorrichtung zusammenwirken,
um den dünnwandigen Behälter an gewünschten Punkten zerbrechen zu lassen, wobei die
Abschnitte so ausgelegt sind, dass der dünnwandige Behälter zusammengedrückt werden
kann, nachdem der Behälter zerbrochen wurde, und der Abschnitt (2), welcher den dünnwandigen
Behälter direkt aufnimmt transparente Eigenschaften aufweist, um das äußerliche Lesen
identifizierender Markierungen zu erleichtern, welche den Behälter identifizieren,
der die zu analysierende Probe enthält.
3. Vorrichtung gemäß Anspruch 2, dadurch gekennzeichnet, dass beide Abschnitte desselben mit einem Behälterabschnitt (4) mit flüssigkeitsdichten
Eigenschaften verbunden sind, so dass er die zu analysierende Flüssigkeit aufnehmen
kann, welche in dem dünnwandigen Behälter enthalten ist.
4. Vorrichtung gemäß Anspruch 2 und 3, dadurch gekennzeichnet, dass die zwei verbindenden Abschnitte des Geräts und des Behälterabschnitts zum Aufnehmen
desselben eine Einheit bilden, die aus Plastikmaterial hergestellt ist, wobei die
zwei Hauptabschnitte des Geräts gelenkig miteinander und dem Behälterabschnitt verbunden
sind.
5. Vorrichtung gemäß Anspruch 2 und 3, dadurch gekennzeichnet, dass die zwei Abschnitte gelenkig miteinander verbunden und einer von ihnen einstückig
mit dem Behälterabschnitt zum Aufnehmen der zu analysierenden Flüssigkeit ausgebildet
ist.
6. Vorrichtung gemäß Ansprüchen 2 bis 5, dadurch gekennzeichnet, dass einer der zwei Abschnitte einen axialen Kanal (8) zum Bereitstellen eines Zugangs
für eine Pipettennadel enthält, welche so eingeführt werden kann, dass sie sich in
den Behälterabschnitt hineinerstreckt.
7. Vorrichtung gemäß Ansprüchen 2 bis 5, dadurch gekennzeichnet, dass einer der Abschnitte mit Schneidelementen (9, 10, 11) ausgestattet ist, welche zum
Schneiden oder Perforieren des Behälters, der die zu analysierende Probe enthält,
an den geforderten Punkten in der Lage ist.
8. Vorrichtung gemäß Anspruch 7, dadurch gekennzeichnet, dass ein Abschnitt des Geräts mit Aussparungen (13, 14) ausgestattet ist, welche mit den
Schneidelementen des anderen Abschnitts zum Zweck des Komprimierens und Schneidens
des Behälters zusammenwirken, der die zu analysierende Flüssigkeit enthält.
9. Vorrichtung gemäß Ansprüchen 2 bis 8, dadurch gekennzeichnet, dass Haltemittel (15, 16) zwischen zwei einstückigen Abschnitten des Geräts vorgesehen
sind, um diesen zu ermöglichen, in einer Position festgestellt zu werden, nachdem
sie miteinander in Eingriff gebracht wurden.
10. Vorrichtung gemäß Ansprüchen 2 bis 9, dadurch gekennzeichnet, dass die zwei einstückigen Abschnitte und der Behälterabschnitt zum Bilden einer Einheit
miteinander in Eingriff gebracht werden können, deren Gesamtform ähnlich der eines
Probenröhrchens ist.
1. Procédé pour extraire et manipuler des liquides biologiques contenus dans des récipients
tubulaires à paroi mince, et pour manipuler ces derniers, dans lequel un élément tubulaire
à paroi mince est utilisé pour contenir un échantillon de liquide, lequel élément
tubulaire est pourvu extérieurement de repères d'identification et est introduit à
l'intérieur d'un dispositif à parois transparentes, de façon à être centré latéralement
et axialement, lequel dispositif est conçu pour procéder à la rupture maîtrisée du
récipient en un point proche de son extrémité inférieure afin de vider le récipient,
et éventuellement en des points proches de son extrémité supérieure de façon à permettre
une admission d'air, puis pour comprimer transversalement l'élément tubulaire de façon
à comprimer celui-ci, l'élément tubulaire étant logé de manière immobile dans le dispositif
de rupture et de compression pour assurer que les données d'identification de l'échantillon
contenu dans ledit récipient à paroi mince puissent encore être lues.
2. Appareil pour extraire et manipuler des liquides biologiques contenus dans des récipients
tubulaires (1) à paroi mince et pour manipuler ces derniers, par le procédé selon
la revendication 1, ledit appareil comprenant au moins deux portions (2, 3) qui peuvent
être réunies l'une à l'autre, une première portion étant mobile par rapport à l'autre,
et comprenant des moyens pour tenir de manière radiale et axiale le récipient tubulaire
à paroi mince contenant un échantillon de liquide et étant pourvu d'un moyen par lequel
les deux portions du dispositif coopèrent pour provoquer la rupture du récipient à
paroi mince en des points voulus, lesdites portions étant conçues de façon que le
récipient à paroi mince puisse être comprimé après la rupture dudit récipient, et
que la section (2) qui reçoit directement le récipient à paroi mince ait des caractéristiques
de transparence afin de faciliter la lecture, de l'extérieur, de repères d'identification
qui identifient ledit récipient contenant l'échantillon à analyser.
3. Appareil selon la revendication 2, caractérisé en ce que les deux portions de celui-ci sont reliées à une portion formant réservoir (4) ayant
des propriétés d'étanchéité au liquide afin de pouvoir recevoir le liquide à analyser
contenu dans le récipient à paroi mince.
4. Appareil selon les revendications 2 et 3, caractérisé en ce que les deux portions reliées du dispositif et la portion formant réservoir destinée
à recevoir celui-ci constituent un ensemble en matière plastique, grâce à quoi les
deux portions principales du dispositif sont articulées l'une à l'autre ainsi qu'à
la partie formant réservoir.
5. Appareil selon les revendications 2 et 3, caractérisé en ce que lesdites deux portions sont articulées l'une à l'autre et l'une d'elles fait corps
avec la portion formant réservoir pour recevoir le liquide à analyser.
6. Appareil selon les revendications 2 à 5, caractérisé en ce que l'une des deux portions comporte un conduit axial (8) donnant accès à une aiguille
de pipettage qui peut être insérée de manière à s'étendre à l'intérieur de la portion
formant réservoir.
7. Appareil selon les revendications 2 à 5, caractérisé en ce que l'une desdites portions est pourvue d'éléments coupants (9, 10, 11) aptes à couper
ou perforer aux endroits voulus le récipient contenant l'échantillon à analyser.
8. Appareil selon la revendication 7, caractérisé en ce qu'une portion du dispositif est pourvue d'évidements (13, 14) qui coopèrent avec les
éléments coupants de l'autre portion dans le but de comprimer et de couper le récipient
contenant le liquide à analyser.
9. Appareil selon les revendications 2 à 8, caractérisé en ce que des moyens de tenue (15, 16) sont disposés entre les deux parties solidaires du dispositif
pour leur permettre d'être immobilisées après avoir été accouplées l'une avec l'autre.
10. Appareil selon les revendications 2 à 9, caractérisé en ce que les deux portions solidaires et ladite portion formant réservoir peuvent être accouplées
les unes avec les autres pour former un ensemble dont la forme globale est semblable
à celle d'une éprouvette.