Microfluidic flow cell, manufacturing method, use and analysis device

Abstract

The invention relates to a microfluidic flow cell (1a), to a production method for a microfluidic flow cell, to the use of a microfluidic flow cell and to an analysis device. In order to easily produce the flow cell (1a) and to achieve a particularly good complete mixing of the dry substance (10a) arranged in the cavity (9) with the fluid, the passage (7) opens into the cavity (9), and the element (2a) inserted in the passage (7) delimits the cavity (9) by means of a deformable wall (12a).

Description

Technical Field

[0001] The invention relates to a microfluidic flow cell, a method for manufacturing a microfluidic flow cell, an application of the microfluidic flow cell and an analysis device. Background Art

[0002] The flow cell of microfluid (as it is increasingly used as "mini laboratory" for analyzing and / or synthesizing fluids, especially in diagnosis) often contains dry materials, which should be introduced into the flow cell during the manufacture of the flow cell. In order to introduce dry reagents, in the installation step that is still accessible to the cavity, such as the passage or chamber, for accommodating the dry reagents in the flow cell, the reagent liquid to be dried (i.e., the carrier liquid with the reagent dissolved or suspended therein) is transported to the relevant part. Subsequently, the entire component of the flow cell, which is only partially wetted by the reagent liquid, must be dried before it is further installed, and this drying process is usually combined with heat treatment to accelerate or be carried out as a freeze drying process to protect the reagent and take into account stability and resuspension characteristics. Disadvantageously, the flow cell (whose size usually far exceeds the size of the area to be dried only) can occupy a large space in the drying chamber. In addition, the drying process can have an adverse effect on the flow cell itself, especially the sensitive elements installed on the flow cell. Furthermore, during the final installation of the flow cell, the formed dry substance may be damaged by air contact (especially humidity) and welding heat or by the adhesive used during installation, by which the corresponding channel area of ​​the microfluidic flow cell should be hermetically sealed in many cases. For example, a method as described above for introducing dry substances into a flow cell is known from EP 2 198 964 B1. Furthermore, it is also known to preform dry substances into freeze-dried (freeze-dried) balls by using and then introduce them into the flow cell. Summary of the invention

[0003] The object of the present invention is to provide a flow cell of the type mentioned at the outset which is simple to produce and which allows particularly good and thorough mixing of dry material with fluid.

[0004] According to the invention, a flow cell that achieves this object is characterized in that a passage opens into the cavity and that the element inserted into the passage delimits the cavity by means of a deformable wall. The passage makes it particularly easy to introduce dry material into the cavity and the deformable wall adjoining the cavity allows the cavity to be modified and thus the dry material arranged in the cavity to be influenced from the outside, as will be described in more detail below.

[0005] The dry substance is preferably a dry reagent in the form of so-called beads, spheres or pellets, which can be prepared by lyophilization (freeze drying) and have in particular a diameter of 2 to 5 mm. The dry substance is therefore often larger than the adjacent channels of the flow cell.

[0006] In an advantageous embodiment, the deformable wall can be locally concave and surround a portion of the cavity, which portion of the cavity is in particular in the shape of a cylinder or a spherical segment. As a result, a relatively large volume of dry material can be arranged near the deformable wall and influenced by the deformable wall. In addition, a relatively large volume change can be achieved when the deformable wall is moved, which in particular can minimize dead volumes and thus reduce air inclusions and also achieve a pump effect for transporting the supplyable fluid.

[0007] In a particularly advantageous embodiment, the dry substance can be arranged on the inner side of the deformable wall facing the cavity, in particular on a concave section of the deformable wall. It is further advantageous if the deformable wall at least partially surrounds the dry substance in order to hold the dry substance in a frictionally and / or positively locking manner. This allows the dry substance to be positioned at a defined position in the flow cell and also simplifies the manufacture of the flow cell, as will be described below.

[0008] The insert element can have a recess on the outside facing away from the cavity, which recess can be designed, for example, cylindrical and preferably adjoins the deformable wall. When using the flow cell, the components described in detail below can extend into the recess to move the deformable wall and / or act on the dry material arranged in the cavity.

[0009] The insert element can preferably be made in one piece, in particular from silicone, thermoplastic elastomer (TPE) or thermoplastic polyurethane (TPU) and formed, in particular, by injection molding. This allows for cost-effective prefabrication of the element that is subsequently to be inserted into the flow cell.

[0010] Furthermore, a method for producing a microfluidic flow cell is described, which method is characterized in that the dry substance is introduced into the cavity through the through-hole. As a result, the flow cell can be produced substantially without dry substance before the dry substance is introduced in the last step and the through-hole is closed by means of the insertion element. In particular, adverse effects on the dry substance during the production of the flow cell can be excluded.

[0011] A particularly simple production can be achieved by first connecting the dry substance to the element to be inserted and then inserting the dry substance together with the element into the passage. The element to be inserted protects the dry substance from external influences until the element together with the dry substance is inserted into the flow cell. Furthermore, the element with the dry substance can be inserted particularly easily by machine, since the element to be inserted has a defined shape and can also be easily grasped by machine.

[0012] It is particularly advantageous if the dry substance can be held in the element in a friction-locking and / or form-locking manner. This is achieved by the dry substance elastically deforming the deformable wall of the element to be inserted. If the geometry of the element to be inserted and in particular the deformable wall are adapted to the dry substance in such a way that the dry substance engages from behind, the dry substance is also held in a form-locking manner. This makes it particularly easy to prefabricate and store the element to be inserted with the dry substance, thereby preventing the dry substance from accidentally falling off the element to be inserted before it is mounted on the flow cell.

[0013] Additionally or alternatively, the dry substance can be held magnetically and / or electrostatically when inserted into the cavity. Additional magnetically active elements can be provided, which include permanent magnets and / or electromagnets.

[0014] Furthermore, the use of a microfluidic flow cell for analyzing a sample is claimed, characterized in that the deformable wall is moved in order to distribute the dry substance in the fluid supplied to the cavity. The deformable wall makes it particularly easy to apply mechanical forces to the dry substance and / or the fluid arranged in the cavity, thereby accelerating the distribution of the dry substance in the fluid. The deformable wall can also be moved so as to extend into the channel, thereby reducing the channel cross section and promoting the distribution of the dry substance. Alternatively or additionally, the dry substance can also contain magnetically active components, which are magnetically loaded by the deformable wall so that the dry substance is distributed in the supplied fluid. The magnetic loading of the dry substance in the flow cell is an independent invention, regardless of whether an insertion element and a deformable wall are present.

[0015] It is particularly advantageous that the deformable wall can be moved elastically, preferably to such an extent, that the dry matter is pressed against the wall of the flow cell and thus comminuted. The distribution of the dry matter in the supplied fluid is also accelerated by this mechanical comminution of the dry matter.

[0016] The deformable wall can be moved successively in different, preferably opposite directions, in order to alternately increase and decrease the volume of the cavity, thereby achieving a pump effect which moves the supplied fluid in the cavity and the at least one adjacent channel, which additionally accelerates the distribution of the dry substance in the fluid.

[0017] It can be particularly advantageous to provide that the fluid is not supplied to the cavity until the cavity has been reduced by the deformable wall. This avoids unnecessary dead volumes and thus, for example, avoids air accumulation in the cavity. The supply of fluid can be achieved by elastic resetting of the deformable wall and the negative pressure thus generated in the cavity. Alternatively or additionally, a negative pressure can also be applied to the outer side of the deformable wall, which causes the deformable wall to retract.

[0018] In addition, it is also claimed that a kind of analysis device for analyzing samples by means of the flow cell of the above-mentioned microfluid is characterized in that an operating device for moving a deformable wall is provided. The operating device can advantageously have a movable push rod and / or a tube for applying negative pressure and / or overpressure to move the deformable wall. In addition, the analysis device can include at least one magnetically active element acting on a dry substance. Therefore, a magnetically active component, such as a metal part, can be set in the dry substance, which can be magnetically held or moved to keep the dry substance at a specific position or promote the distribution of the dry substance in the fluid. The analysis device can include at least one input and / or output pipeline for entering or leaving the flow cell for a sample, and / or a sensor for determining the position of a fluid or sample in the flow cell or for analyzing a sample processed in the flow cell. The input and / or output pipeline can be pressed onto the flow cell to produce an airtight sealed connection. Reference LU502668, the content of which is incorporated into this application. There, further embodiments and uses of a flow cell according to the invention with an insert element (referred to there as reagent plug, RP for short) and a movable wall (referred to there as flexible wall, FW for short) and a corresponding analytical device are shown. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features and advantages of the present invention are derived from the following description of preferred embodiments with reference to the accompanying drawings. The accompanying drawings are as follows:

[0020] Figure 1 shows a longitudinal section through a flow cell with an insert element and a dry substance according to a first embodiment;

[0021] Figure 2 shows a longitudinal section through a flow cell with an insert element and dry material according to a second embodiment;

[0022] Figure 3 shows a longitudinal section through a flow cell with an insert element and without dry matter according to a third embodiment;

[0023] Figure 4 Show Figure 3 A longitudinal cross-section of a flow cell with dry material is shown;

[0024] Figure 5 shows a longitudinal section through a flow cell with an insert element and a dry substance according to a fourth embodiment;

[0025] Figure 6 Show Figure 5 A longitudinal cross-sectional view of a flow cell with an attached magnet;

[0026] Figure 7 Show Figure 5A longitudinal cross-sectional view of a flow cell with a supplied fluid;

[0027] Figure 8 Show Figure 7 A longitudinal cross-sectional view of a flow cell with a pneumatic operating device;

[0028] Fig. 9 Show Figure 7 A longitudinal cross-sectional view of a flow cell with an electromechanical operating device;

[0029] Fig.10 Show Figure 1 A longitudinal cross-sectional view of a flow cell with a supplied fluid and an operating device in a first operating position;

[0030] Fig.11 Show Figure 1 A longitudinal cross-sectional view of a flow cell with an operating device in a second operating position;

[0031] Fig.12 Show Figure 7 A longitudinal cross-sectional view of a flow cell with an operating device; and

[0032] Fig.13 The sequence of three steps is shown when preparing a unit from insert elements and dry substance. DETAILED DESCRIPTION

[0033] exist Figure 1 , a longitudinal section of a flow cell 1a with an insert element 2a according to a first embodiment is shown. The flow cell 1a comprises a substantially flat planar substrate 3 in a known manner, which is covered on its underside by a film 4. The film 4 is preferably welded or bonded to the substrate 3. At least one channel 5 is provided in the substrate 3, which is delimited by the film 4. Such a flow cell 1a can be easily manufactured in that the substrate is preferably injection molded from plastic and the channel 5 open to the outside is then covered with a film 4 so that the liquid in the channel 5 can be reliably supplied and discharged through the inlet and outlet. The substrate 3 can be made of plastic such as PP, PC, PMMA, COC, COP or PS and the insert element 2a can be made of thermoplastic elastomer PU, TPE, silicone, or vice versa. A detection area for analyzing a mixture consisting of a sample and a dry substance can be provided in an area of ​​the substrate 3 that is not shown.

[0034] On the side of the substrate 3 facing away from the film 4, the substrate 3 comprises a protruding, preferably annular sleeve 6, through which an outwardly open passage 7 leads into the channel 5. The element 2a is inserted from the outside into the passage 7, and a laterally protruding annular flange 8a rests on the sleeve 6 and thus forms a depth limiter for the element 2a inserted into the sleeve 6. In addition or alternatively, a depth stop can also be realized on the passage. A cavity 9 is preferably delimited by the element 2a in the passage 7, which also extends into the insertion element 2a, in which a spherical dry substance 10a is arranged. An annular groove 11a is arranged on the outer side of the insertion element 2a around the cavity 9 in the upper region, which is separated from the cavity 9 by a thin wall. The contour of the insertion element 2a is roughly W-shaped in the longitudinal section shown here. The wall 12a of the insertion element 2a, which rests against the dry material 10 and surrounds it, is designed to be deformable, for example made of an elastic material such as silicone, TPE or TPU, so that the dry material 10a can be loaded with forces from the outside in a particularly simple manner. The walls of the insertion element 2a are arranged at right angles to each other in a longitudinal section. The insertion element 2a is characterized in that Figure 1 In a horizontally extending cross section and in the other figures, it preferably has a circular, rotationally symmetrical shape.

[0035] exist Figure 1 In the embodiment and in the other embodiments described below, the surface of the insertion element facing the cavity and / or the surface of the channel can be hydrophilically modified, for example by non-permanent surface activation by plasma treatment, or coated (permanently, for example by plasma polymerization or coating with a suitable liquid) to facilitate the introduction of the sample and / or the redissolution of the dry substance. The pretreatment of the hydrophilic surface properties can include a contact angle with water of <60°, preferably <30° (wet chemistry, plasma treatment, corona treatment, glass-like coating, for example by plasma polymerization or coating with metal, for example by means of pressure or thin film technology). In addition, the surface of the insertion element can preferably be configured flush with one of the walls of the channel.

[0036] exist Figure 2 1 shows a longitudinal section through a flow cell 1b with an insert element 2b and dry material 10b according to a second embodiment. As in the following figures, the base 3 with the sleeve 6 and the channel 5 with the through-hole 7 and the membrane 4 are designed identically, and therefore the same reference numerals are used. Figure 1 As can be seen from the comparison of the implementation methods, Figure 2The embodiment of the insertion element 2b shown in the figure is different in particular in that the deformable wall 12b (which rests on the dry material 10b) is designed to be curved, especially arched, in the longitudinal section and thus rests on the spherical dry material 10b over the entire surface. In order to ensure the depth of the insertion element 2b in the through-hole 7, the element 2b also includes a laterally protruding annular flange 8b. The corresponding annular groove 11b is constructed according to the curved contour of the deformable wall 12b. In addition, an annular seal 13 is also shown, which is arranged in an annular groove on the end face of the insertion element 2b facing the substrate 3 and can achieve a reliable seal between the substrate 3 and the insertion element 2b. Such an annular seal can also be provided in the embodiments of the insertion element shown in the other figures, even if this is not shown in all figures for the sake of simplicity.

[0037] exist Figure 3 and 4 A longitudinal cross-sectional view of a flow cell 1c according to a third embodiment is shown in FIG. Figure 3 In FIG. 1 , a flow cell 1 c is shown with an insert element 2 c without dry material and in FIG. Figure 4 FIG. 1 shows a flow cell with a dry substance 10c. Figure 3 and 4 As can be seen from the comparison of the deformable wall 12c of the element 2c, initially the deformable wall 12c is flat and is delimited on the outside by a cylindrical recess 14 inserted into the element 2c. The illustrated position of the deformable wall 12c corresponds to a state in which the previously present dry substance has completely dissolved in the supplied fluid and has already been discharged through the channel 5. In contrast, in Figure 4 1 shows a flow cell 10c after production, which has an insert element 2c and a dry substance 12c arranged in the cavity 9. The dry substance 12c here rests on the membrane 4 and is pressed against the deformable wall 12c, which is preferably elastically curved outward in the direction of the recess 14a. Due to this prestressing, the mechanical comminution of the dry substance 10c is simplified by the additional forces acting from the outside on the deformable wall 12c and the dead volume is reduced, so that the required fluid is reduced.

[0038] exist Figure 5 , 6 7 show a flow cell 1d according to a fourth embodiment with an insert element 2d and a dry substance 10d in the form of a plurality of pellets. The individual pellets of dry substance 10d can be influenced magnetically, i.e. contain magnetic components (e.g. permanent magnets) or include magnetizable components (e.g. metals). Figure 3 and 4In this case, after the production of the flow cell 1d, the dry substance 10d consisting of pellets is held on a deformable wall 12d in a cavity 9 (here without a reference numeral) by magnetic force or other means, for example by an adhesive or a releasable bonding agent. In this case, some pellets of the dry substance 10d also extend into the channel 5, which is advantageous when the dry substance 10b is subsequently distributed and dissolved in the supplied fluid.

[0039] exist Figure 6 14b and 14c. A magnet 15 is additionally shown, which extends into the recess 14b and rests on the deformable wall 12d opposite the dry substance 10d on the outside. The magnet 15 (which can be configured as a permanent magnet or an electromagnet) can cause a magnetic force, in particular an attractive force and / or a repulsive force, to act on the dry substance 10d. This can promote the distribution of the dry substance 10d in the supplied fluid and in addition, the components of the dry substance 10d that are not dissolved in the fluid can be collected and retained again by the magnet 15. The magnet 15 can additionally press against the deformable wall 12d here to cause the movement of the deformable wall 12d and thus the dry substance 10d and the supplied fluid, thereby additionally promoting the distribution of the dry substance in the fluid. In addition, the channel cross section is reduced by the wall 12d deforming in the channel direction, thereby also increasing the magnetic effect in the channel 5.

[0040] exist Figure 7 1 shows a possibility of distributing or dissolving a dry substance 10d formed as pellets by moving a fluid 16 arranged in a channel 5. The fluid 16 can here preferably be moved back and forth periodically, for example by an overpressure applied alternately to the ends of the channel 5. In addition, as in Figure 7 As shown in FIG. 1 , a magnet 15 can also be provided which acts on the dry material 10 d magnetically and, if appropriate, by movement.

[0041] exist Figure 8 and 9 The longitudinal section is shown in Figure 7 Flow cell 1d with different operation devices. Figure 8 In the embodiment shown in FIG. 1 , a pneumatic operating device 17a is provided, which is sealingly attached to the insert element 2d, in particular to the annular flange 8d, and is designed to generate a negative pressure and / or an overpressure in the recess 14b. Since the recess 14b is sealed airtightly by the pneumatic operating device 17a, the overpressure and / or underpressure leads to a movement of the deformable wall 12d indicated by the arrow, whereby the dry substance 10d configured as pellets is particularly well distributed in the fluid 16. If the negative pressure and / or overpressure is periodically established, the deformable wall 12d and thus the fluid 16 can also vibrate, which additionally promotes the distribution of the dry substance 10d.

[0042] exist Fig. 9 A mechanical operating device 17b is provided in the embodiment of the present invention, which is configured as a push rod, for example, and extends into the recess 14b and abuts against the deformable wall 12d. When the mechanical operating device 17b moves in the direction of the deformable wall 12d, the deformable wall 12d deflects and thus also transmits the movement to the dry material 10d and the fluid 16. The movement of the mechanical operating device 17b can also be performed periodically in order to additionally promote the distribution of the dry material 10d in the fluid 16.

[0043] exist Fig.10 and 11 Shown in Figure 1 A flow cell 1a with a supplied fluid and an operating device 17c in different operating positions. Fig.10 In the operating position shown in FIG. 1 , the schematically shown operating device 17 c (which can be a pneumatic or mechanical operating device) is arranged to load the deformable wall 12 a in the direction of the dry substance 10 a. The deformable wall 12 a and the initially spherical dry substance 10 a are already deformed. Starting from a certain degree of deformation, the dry substance 10 a is comminuted into a plurality of small parts which are particularly well distributed or dissolved in the fluid 16. This state is Fig.11 , in which the deformable wall 12 a completely fills the through-hole 7 and the cavity 9 , so that only the channel 5 in which the fluid 16 is arranged remains and the dry substance 10 a is completely distributed or dissolved in the fluid 16 .

[0044] exist Fig.12 Shown in Figure 7 14d, longitudinal section of a flow cell with an operating device 17d. As shown, a tube 18, which is only partially shown here, rests sealingly on the insertion element 2b, in particular on the annular flange 8d, through which negative pressure and / or overpressure can be introduced into the recess 14d, so that the deformable wall 12d moves as described above. In addition, a magnet 19, for example in the form of a rod, is preferably arranged concentrically in the tube 18, which extends into the recess 14b and rests on the outside of the deformable wall 12d. As a result, the magnetic components of the dry material 10d can be retained and also moved by the negative pressure and / or overpressure that can be introduced into the tube 18.

[0045] exist Fig.13, the sequence of three steps when prefabricating a unit from an element to be inserted (here, the element to be inserted 2b is used as an example) and a dry substance (here, the dry substance 10b is used as an example). As can be seen from the left figure, in the first step, the dry substance 10b is inserted into the cavity 9 of the element 2b and preferably held there in a form-locking and / or friction-locking manner. The unit prefabricated in this way can be seen in the middle figure, which unit can also be stored without any problems. The last step is shown in the right figure, in which the prefabricated unit is inserted into the through-hole 7 in the flow cell sleeve 6. Through this prefabrication, in particular, contamination of the dry substance 10b and mechanical stress during storage and transportation can also be reliably avoided, because the dry substance 10b is not directly, but only grasped and held by the element 2b.

[0046] The embodiments shown in the various figures can be combined without any problem. For example, different operating devices can also be arranged on the remaining insertion elements. Different insertion elements and different operating devices can therefore be combined in any variation.

[0047] Reference numerals list

[0048] 1a, 1b, 1c, 1d flow cell

[0049] 2a, 2b, 2c, 2d Insert components

[0050] 3 base

[0051] 4 films

[0052] 5 channels

[0053] 6 sleeves

[0054] 7Through

[0055] 8a, 8b, 8c, 8d annular flange

[0056] 9 Cavity

[0057] 10a, 10b, 10c, 10d Dry substances

[0058] 11a, 11b annular groove

[0059] Walls 12a, 12b, 12c, 12d

[0060] 13 Ring seal

[0061] 14a, 14b notches

[0062] 15 Magnets

[0063] 16 Fluid

[0064] 17a, 17b, 17c, 17d operating device

[0065] 18 tubes

[0066] 19 Magnet

Claims

1. A microfluidic flow cell (1a; 1b; 1c; 1d), comprising a dry substance (10a; 10b; 10c; 10d) arranged in a cavity (9) within the flow cell (1a; 1b; 1c; 1d), the dry substance being adapted to interact with a fluid (16) that can be supplied to the cavity (9), It is characterized in that The through-hole (7) opens into the cavity (9), and the element (2a; 2b; 2c; 2d) inserted into the through-hole (7) delimits the cavity (9) by means of a deformable wall (12a; 12b; 12c; 12d).

2. The flow cell (1a; 1b) according to claim 1, characterized in that The deformable wall (12a; 12b) is at least partially concave and surrounds at least a portion of the cavity (9).

3. The flow cell (1a; 1b) according to claim 1 or 2, characterized in that The deformable wall (12a; 12b) surrounds a portion of the cavity (9), and in particular, this portion of the cavity is configured in the shape of a cylinder or a spherical segment.

4. A flow cell (1a; 1b; 1c; 1d) according to any one of the preceding claims, characterized in that The dry substance (10a; 10b; 10c; 10d) is arranged on the inner side of the deformable wall (12a; 12b; 12c; 12d) facing the cavity (9), in particular on a concave section of the deformable wall (12a; 12b).

5. The flow cell (1a; 1b) according to claim 4, characterized in that The deformable wall (12a; 12b) at least partially surrounds the dry substance (10a; 10b).

6. A flow cell (1a; 1b; 1c; 1d) according to any one of the preceding claims, characterised in that The inserted element (2a; 2b; 2c; 2d) has a recess (14a; 14b) on the side facing away from the cavity (9), in particular the recess is designed to be cylindrical.

7. A flow cell (1a; 1b; 1c; 1d) according to any one of the preceding claims, characterised in that The inserted elements ( 2 a ; 2 b ; 2 c ; 2 d ) are made of silicone, TPE, TPU and are formed in particular by injection molding.

8. A method for manufacturing a microfluidic flow cell (1a; 1b; 1c; 1d) according to any one of claims 1 to 7, characterized in that: The dry substance (10a; 10b; 10c; 10d) is introduced into the cavity (9) through the through-hole (7).

9. The method according to claim 8, characterized in that The dry substance (10a; 10b; 10c; 10d) is first connected to the element (2a; 2b; 2c; 2d) and then the dry substance is inserted into the passage (7) together with the element (2a; 2b; 2c; 2d).

10. The method according to claim 9, characterized in that The dry substance (10a; 10b; 10c; 10d) is held in an element (2a; 2b; 2c; 2d) in a friction-locking and / or form-locking manner.

11. The method according to any one of claims 8 to 10, characterized in that The dry substance (10a; 10b; 10c; 10d) is held magnetically and / or electrostatically when inserted into the cavity (9).

12. Use of the microfluidic flow cell (1a; 1b; 1c; 1d) according to any one of claims 1 to 7 for analyzing a sample, characterized in that: The deformable wall (12a; 12b; 12c; 12d) is moved so as to distribute the dry substance (10a; 10b; 10c; 10d) in the fluid (16) supplied to the cavity (9).

13. The use according to claim 12, characterized in that: The deformable wall (12a; 12b; 12c; 12d) is moved to such an extent that the dry substance (10a; 10b; 10c; 10d) is pressed against the wall (4) of the flow cell (1a; 1b; 1c; 1d) and the dry substance is thereby comminuted.

14. The use according to claim 12 or 13, characterized in that: The deformable walls (12a; 12b; 12c; 12d) move successively in different directions so as to alternately increase and decrease the volume of the cavity (9).

15. The use according to any one of claims 12 to 14, characterized in that The fluid (16) is supplied into the cavity (9) only after the cavity (9) has been reduced in size by the deformable wall (12a; 12b; 12c; 12d).

16. An analysis device for analyzing a sample by means of a microfluidic flow cell (1a; 1b; 1c; 1d) according to any one of claims 1 to 7, characterized in that: An operating device (17a; 17b; 17c; 17d) is provided for moving the deformable wall (12a; 12b; 12c; 12d).

17. The analysis device according to claim 16, characterized in that The operating device (17a; 17b; 17c; 17d) has a movable push rod (17b; 17c; 19) and / or a tube (18) for applying negative pressure and / or overpressure to move the deformable wall (12a; 12b; 12c; 12d).

18. The analysis device according to claim 16 or 17, characterized in that A magnetically active element (19) is provided which acts on the dry material (10a; 10b; 10c; 10d).

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