NEW MULTI-FUNCTIONAL FLUIDIC DEVICE FOR CLAMPING BIOPSIES

Abstract

A fluidic device (1) comprises a flow chamber (2) for accommodating a biological specimen on a carrier portion (3) and at least one flow channel (4a, 4b, 4c, 4d) fluidly connected to the flow chamber (2), the fluidic device (1) having a layered structure comprising a bottom plate (5), a cover plate (6) and an insert (7) in between, the insert (7) comprising the carrier portion (3) and a frame portion surrounding the carrier portion (3), and being elastomeric in order to be able to clamp a biological specimen between an incision in the carrier portion (3).

Claims

1. A fluidic device comprising: a flow chamber for accommodating a biological specimen on a carrier portion and at least one flow channel fluidly connected to the flow chamber, the fluidic device having a structure comprising a bottom plate, a cover plate and an insert in between the bottom plate and the cover plate, the insert comprising the carrier portion and a frame portion surrounding the carrier portion, the carrier portion comprising an elastomeric material, wherein the carrier portion is provided with an incision for accomodating the biological specimen.

2. The fluidic device of claim 1, wherein the frame portion comprises a further elastomeric material, wherein preferably the further elastomeric material is the same as the elastomeric material.

3. The fluidic device of claim 1, wherein the carrier portion and/or the frame portion is characterized by a Shore A hardness within the range of 2 to 80.

4. The fluidic device of claim 1, wherein the incision defines an opening in the carrier portion when the carrier portion is in an undeformed state.

5. The fluidic device of claim 1, wherein the elastomeric material and/or the further elastomeric material are chosen from the group consisting of thermoplastic elastomers and elastomers like silicones and polybutadiene rubbers, wherein the thermoplastic elastomers are preferably selected from the group consisting of styrenic block copolymers (TPS), preferably styrene ethylene butylene styrene block copolymers (SEBS), and thermoplastic polyurethanes (TPU).

6. The fluidic device of claim 1 wherein the carrier portion is porous, or microporous.

7. The fluidic device of claim 1, wherein the flow chamber and the at least one flow channel are formed by structuring a lower surface and/or on an upper surface of the insert.

8. The fluidic device of claim 1, wherein the microporous carrier portion separates the flow chamber in a lower flow chamber region and an upper flow chamber region, and wherein at least one lower flow channel is preferably fluidly connected to the lower flow chamber region and at least one upper channel is fluidly connected to the upper flow chamber region.

9. The fluidic device of claim 1, wherein the bottom plate and/or the cover plate comprises at least one port fluidly connected to the at least one flow channel.

10. The fluidic device of claim 1, wherein the bottom plate and/or the cover plate is UV/VIS transparent.

11. The fluidic device of claim 1, wherein the bottom plate and/or the cover plate has a layer thickness of 0.5 to 20 mm, preferably 0.8 to 15 mm, more preferably 1 to 10 mm and most preferably 2 to 6 mm, and/or wherein the insert has a layer thickness, when measured at the thickest point, of 0.5 and 20 mm, preferably 1 to 15 mm, more preferably 2 to 10 mm and most preferably 3 to 8 mm and/or wherein the insert has a layer thickness, when measured at the thinnest point, of 0.1 and 5 mm, preferably 0.1 to 3 mm, more preferably 0.2 to 2 mm and most preferably 0.3 to 1 mm.

12. An insert for a microfluidic device, the insert comprising: a carrier portion and a frame portion surrounding the carrier portion, the insert comprising an elastomeric material, and wherein the carrier portion is provided with an incision for accomodating a biological specimen, optionally wherein the insert is further defined in claim 2.

13. The insert of claim 11, wherein the insert contains a plurality of carrier portions, each carrier portion being surrounded by the frame portion.

14. A system or kit comprising an insert, a bottom plate and a cover plate, wherein the bottom plate, the insert and the cover plate, when stacked in this order, form a fluidic device as defined in claim 1.

15. The system or kit of claim 14, further comprising: a fluidic device comprising: a flow chamber for accommodating a biological specimen on a carrier portion and at least one flow channel fluidly connected to the flow chamber, the fluidic device having a structure comprising a bottom plate, a cover plate and an insert in between the bottom plate and the cover plate, the insert comprising the carrier portion and a frame portion surrounding the carrier portion, the carrier portion comprising an elastomeric material, wherein the carrier portion is provided with an incision for accomodating the biological specimen. an insert for a microfluidic device, the insert comprising: a carrier portion and a frame portion surrounding the carrier portion, the insert comprising an elastomeric material, and wherein the carrier portion is provided with an incision for accomodating a biological specimen, and a holder for holding the fluidic device.

16. A method for clamping a biological specimen, preferably a biopsy, comprising: providing an insert as defined in claim 11, wherein the microporous carrier portion of the insert is provided with an incision for accomodating the biological specimen, and clamping the biological specimen between adjacent cut ends defined by the incision.

17. Use of a fluidic device as claimed in claim 1, or: an insert for a microfluidic device, the insert comprising: a carrier portion and a frame portion surrounding the carrier portion, the insert comprising an elastomeric material, and wherein the carrier portion is provided with an incision for accomodating a biological specimen, or a system or kit comprising an insert, a bottom plate and a cover plate, wherein the bottom plate , the insert and the cover plate, when stacked in this order.

18. Method of manufacturing a insert for a microfluidic device comprising the step of crating an incision within a region of a carrier portion of an insert comprising the carrier portion and a frame portion surrounding the carrier portion, where the insert comprises or consists of an elastomeric material and the carrier portion includes a region for making an incision.

19. Method of manufacturing a microfluidic device or a kit for a microfluidic device comprising the method of claim 18.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] FIG. 1 shows an example of a fluidic device as disclosed herein;

[0044] FIG. 2 shows a further example of a fluidic device as disclosed herein;

[0045] FIGS. 3 and 4 respectivly show exploded bottom and top view of the fluidic device of FIG. 1;

[0046] FIG. 5 shows another example of a fluidic device as disclosed herein;

[0047] FIG. 6 shows yet another example of a fluidic device as disclosed herein;

[0048] FIG. 7 shows a sectional view of the fluidic device shown in FIG. 1;

[0049] FIGS. 8A and 8B show a top views of a part of a flow chambers having microporous carrier portions;

[0050] FIG. 9 shows an insert comprising a plurality of carrier portions;

[0051] FIG. 10 shows force-strain measurement results obtained by pushing a pen with rounded tip and a diameter of 1.2 mm in the thickness direction onto and through an opening in a membrane incision that was pre-cut in an insert, wherein FIG. 10A illustrates the measurement by showing pen positions at different time points, and wherein FIG. 10B is a graph of force (F) versus strain (Δl); and

[0052] FIG. 11 shows results on force-strain measurements for a case where an insert having an incision as disclosed herein is stretched by pulling opposite ends of the insert away from each other in opposite directions, wherein FIG. 11A illustrates the measurement by showing the resulting opening at different time points during the measurement, and wherein FIG. 11B is a graph depicting force (F) versus strain (Δl).

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0053] Referring to FIG. 1, a fluidic device 1 as disclosed herein comprises a flow chamber 2 for accommodating a biological specimen on a microporous carrier portion 3 and at least one flow channel 4, 4a, 4b, 4c, 4d fluidly connected to the flow chamber 2. The fluidic device 1 has a layered structure comprising a bottom plate 5, a cover plate 6 and an insert 7 in between, as can be best seen from the exploded views of FIGS. 3 and 4. Further, the insert 7 comprises a microporous carrier portion 3 and a frame portion 8 surrounding the microporous carrier portion 3 and is modified or modifiable with an incision 9 provided in the microporous carrier portion 3, as can be seen in FIG. 2. In accordance with the present invention, the insert 7 is elastomeric so as to provide a clamping mechanism for a biological specimen as described herein.

[0054] To prevent damage of a biological specimen, the insert 7 is adapted so that the opening defined by the incision 9 can be widened to an extent sufficient to place the biological specimen in between using low force. This is particularly useful when handling a biopsy which is generally very weak and sensitive to mechanical stress. The extent of widening and the required force depends on the way how the incision 9 is forced to be opened.

[0055] In a case where opposing edges of the insert 7 are pulled in opposite directions away from each other, the force is preferably 5 N or less, more preferably 2.5 N or less and most preferably 1 N or less and/or at least 0.4 N, preferably at least 0.6 N. These values in particular apply when the width of the opening defined by the incision 9 is widened to 0.2 to 3 mm, preferably 0.4 to 2 mm, more preferably 0.5 to 1.5 mm and most preferably 1 mm 0.2 mm.

[0056] In a case where a pushing force is exerted in the thickness direction of the insert 7 directly onto the incision 9 or in immediate proximity thereto using, e.g., tweezers, the force is preferably 50 mN or less, more preferably 10 mN or less and most preferably 5 mN or less and/or at least 0.5 mN, preferably at least 1 mN.

[0057] In a case where a bending force is exerted along an axis extending through the microporous carrier portion 3 so that the insert 7 bends by at least 60°, preferably at least 90°, more preferably at least 120°, even more preferably at least 150° and most preferably about 180° C., the force when grasping opposing edges of the insert 7 by a thumb and a forefinger is preferably 1000 mN or less, more preferably 500 mN or less and most preferably 200 mN or less and/or at least 2 mN, preferably at least 5 mN.The flow chamber 2, as disclosed herein, denotes a (micro-) structured region within the fluidic device 1, which has a volume sufficient to accommodate a biological specimen 10, preferably a biopsy such as a prostate biopsy, and at least one inlet and/or at least one outlet connecting to the at least one channel 4a, 4b, 4c, 4d. Preferred flow chambers 2 have a volume of 50 to 1000 mm.sup.3, for example 100 to 500 mm.sup.3. In specific embodiments, the flow chamber 2 further provides a micro-environment that enables a biological specimen 10 to be cultivated and/or to retain functional activity. In this case, the microporous carrier portion 3 may be provided with a correspondingly functionalized surface. For instance, the microporous carrier portion 3 may be functionalized with collagen gel or fibronectin. In this way, cells or tissue may be accommodated in an environment similar to their naturally occurring environment, which is particularly useful when the fluidic device is used for cultivating the biological specimen (cells or tissue) for organ replacement/transplantation (organ-on-a-chip), performing ex-vivo chemotherapy on the biological specimen or testing pharmaceuticals on the biological specimen. Suitable functionalization agents and methods are disclosed, for instance, in PCT application WO2019/015988, titled “Cell culturing materials”, which disclosure is herein incorporated by reference in its entirety, in particular for the purpose of disclosing agents and methods for functionalizing an insert for a fluidic device.

[0058] According to the shown embodiment, the flow chamber 2, when viewed from the top, has an essentially circular form. More precisely, the flow chamber 2 preferably has a shape of a flat cylinder. The flow chamber 2 can have a diameter of, for example, 2 to 30 mm, preferably 3 to 20 mm and more preferably 4 to 15 mm. Other shapes are also envisaged such as ellipsoid or rectangular forms.

[0059] A microporous carrier portion 3 and a frame portion 8, as disclosed herein, can be best seen in FIG. 2. Here, it can also be seen that the at least one channel 4a, 4b (an inflow channel and an outflow channel in the embodiment of FIG. 2) branches off from the flow chamber 2 and extends into the frame portion 8. Preferably, the bottom plate 5 and the cover plate 6 are relatively stiff, whereas the insert 7 is relatively soft, as will be further explained herein. With continuing reference to FIG. 2, it can be seen that an incision 9 is preferably provided in the microporous carrier portion 3.

[0060] The term “one channel” as used herein denotes a configuration that provides s single channel for inflow and outflow of fluids and a configuration that provides a pair of channels, one of which is provided for inflow of fluids (inflow channel) and the other one being provided for outflow of fluids (outflow channel). A configuration comprising such pair of inflow channel 4a and outflow channel 4b can be seen in FIG. 3. A configuration comprising two pairs of channels, each pair comprising an inflow channel 4a, 4c and a separate outflow channel 4b, 4d is best seen in FIG. 1. Fluidic devices 1 as disclosed herein may comprise 1 flow channel, 2 flow channels, 3 flow channels, 4 flow channels, 5 flow channels, 6 flow channels or even more than 6 flow channels as disclosed above.

[0061] Referring again to the exploded view of the fluidic device 1 shown in FIG. 3, it can be seen that the insert's frame portion 8 is preferably intended to define the chamber's side walls and space apart the bottom plate 5 and the cover plate 6. This means, the flow chamber 2 is enclosed by the upper surface of the bottom plate 5, the lower surface of the cover plate 6 and the inner side walls of the frame portion 8. In the shown embodiment, the frame portion 8 is constituted by the unstructured region of the insert 7. However, it can be readily appreciated that the frame portion 8 can be alternatively formed by an elevation that circumscribes the structured region defining the flow chamber 2 and the at least one flow channel 4 (herein collectively referred to as flow paths 2, 4).

[0062] As can be best seen in FIGS. 3 and 4, the flow chamber 2 and the at least one flow channel 4a, 4b, 4c, 4d of fluidic devices 1 as disclosed herein are preferable formed by structuring the insert 7. However, it is also envisaged that at least one of the bottom plate 5 and the cover plate 6 is structured. In preferred fluidic devices 1, a lower surface of the insert 7 (i.e. surface facing the bottom plate 5) and an upper surface of the insert 7 (i.e. surface facing the cover plate 6) is provided with appropriate structures forming the flow paths 2, 4 as disclosed herein. More specifically, the lower surface of the insert 7 is preferably provided with at least one groove in a region of the frame portion 8 to form the at least one channel 4a, 4b, as shown in FIG. 3. In addition or alternatively, the upper surface of the insert 7 may be preferably provided with at least one groove in a region of the frame portion 8 to form the at least one channel 4c, 4d, as shown in FIG. 4. The cross-sectional shape of the at least one groove corresponding to the at least one channel 4 is not limited, and examples of possible shapes include recessed shapes, U-shapes, and V-shapes. The depth and/or width of the groove is preferably 10 to 2000 μm, more preferably 50 to 1500 μm and most preferably 100 to 1000 μm.

[0063] It is further preferred that a depression is provided on the lower surface (cf. FIG. 3) and/or on the upper surface (cf. FIG. 4) of the insert 7 in a region of the carrier portion 3 to form the flow chamber 2. According to this configuration, the flow chamber 2 is formed by a microporous carrier portion 3 having a lower layer thickness than the layer thickness of the surrounding frame portion 8. Such preferred inserts 7 can be produced by any suitable technique for producing a surface-structured—preferably elastomeric—article. Preferred techniques include, without being limited, molding, 3-D printing, casting and embossing.

[0064] With continuing reference to FIGS. 3 and 4, it can be seen that fluids are preferably supplied through the cover plate 6. For this purpose, the cover plate 6 comprises at least one port 11 that provides fluid access to the at least one flow channel 4a, 4b, 4c, 4d. It can be further seen that the insert 7 may comprise at least one aperture 12 aligning with the at least one port 11, the at least one aperture 12 being fluidly connected to the flow chamber 2 via the at least one flow channel 4. In the embodiment shown in FIGS. 3 and 4, the at least one port 11 and the at least one aperture 12 have a circular shape with coinciding radial axes. Although supply of fluids through the cover plate 6 as disclosed above can be easily implemented and readily used with existing instruments (e.g. fluid device holders), it is also envisaged that fluids can be supplied through the bottom plate 5 or through a side surface of the insert 7, in which case corresponding port(s) 11 is/are present in the bottom plate 5 or the insert 7.

[0065] As shown in FIGS. 5 and 6, the port 11 may be connected to a fitting 13, which is connectable to a tube carrying fluid. The embodiment shown in FIG. 5 has a configuration with 4 fittings 13 providing fluid access to a lower flow channel (not seen in FIG. 5) and an upper flow channel 4c, 4d, as disclosed herein. It can be further seen that the cover plate 6 is provided with a plurality of ports 11, whereas the number of functional ports (i.e. ports providing fluid access to the flow chamber 2 via the at least one flow channel 4a, 4b, 4c, 4d) is governed by the structured surface of the insert 7. In this example, the fluidic device 1 comprises 4 functional ports and 8 dead-end ports 11a, which do not align with a corresponding aperture 12 of the insert 7 and are therefore not functional. In the configuration shown in FIG. 6, all 12 ports are provided with fittings 13 and are functional. The structuring of the insert 7 is not shown. This embodiment has the advantage in that an equally configured cover plate 6 can be used irrespective of the desired number of ports being functional.

[0066] The insert 7 is preferably a flat cuboid with an upper surface and a lower surface facing a lower surface of the cover plate 6 and an upper surface of the bottom plate 5, respectively. In the upper surface of the flat cuboid and/or lower surface of the flat cuboid structured regions are provided that form flow paths 2, 4 as disclosed herein. It is further preferred that the upper and the lower surfaces of the insert 7 are rectangular with a longer and a shorter edge length, and that the incision is provided substantially parallel (±45°, preferably ±30° and more preferably ±20° to the shorter edge length. Other shapes, such as a flat cuboid shape with rounded edges or a flat cylindrical shape, with corresponding structures as described above are conceivable as well. It is further preferred that the shape of the insert 7 is such that its upper and lower surfaces correspond to the lower surface of the cover plate 6 and the upper surface of the bottom plate 5, respectively.

[0067] The layer thickness of the—preferably flat cuboid—insert 7 can, when measured at the thickest point, range between 0.5 and 20 mm, and is preferably 1 to 15 mm, more preferably 2 to 10 mm and most preferably 3 to 8 mm. The layer thickness of the insert 7 can, when measured at the thinnest point, range between 0.1 and 5 mm, and is preferably 0.1 to 3 mm, more preferably 0.2 to 2 mm and most preferably 0.3 to 1 mm. In preferred fluidic devices 1, the thickest point lies in the frame portion 8 and the thinnest point lies in the carrier portion 3. In this case, the carrier portion 3 may have, for example, a thickness that is 5 to 50% of the thickness of the frame portion 8.

[0068] A preferred fluidic device 1 as disclosed herein comprises a planar bottom plate 5 and/or a planar cover plate 6, wherein the planar bottom plate 5 and/or the planar cover plate 6 has a flat cuboid shape with optionally rounded edges or a flat cylindrical shape as described above with respect to the insert 7. The thickness of the—preferably flat cuboid—bottom plate 5 and/or cover plate 6 can be in a range of 0.5 and 20 mm, and is preferably 0.8 to 15 mm, more preferably 1 to 10 mm and most preferably 2 to 6 mm.

[0069] Referring now to FIG. 7, a sectional view of the fluidic device 1 shown in FIGS. 3 and 4 is shown. As can be seen, in preferred fluidic devices 1, the carrier portion 3 separates the flow chamber 2 in a lower flow chamber region 2a and an upper flow chamber region 2b. In this case, it is further preferred that at least one lower flow channel 4a, 4b is provided that stands in fluid connection with the lower flow chamber region 2a and at least one upper flow channel 4c, 4d is provided that stands in fluid connection with the upper flow chamber region 2b. According to such configuration, the lower flow chamber region 2a and the upper flow chamber region 2b can be fed with different fluids at the same time as described herein. As also described herein, the at least one channel 4 is preferably a pair of channels, which pair provides an inflow channel 4a, 4c and an outflow channel 4b, 4d.

[0070] Next, the structure of the microporous carrier portion 3 of preferred fluidic devices 1 is described with reference to FIG. 8. The structure is especially such that cross-sectional fluid flow through the insert can occur and thereby constant and reproducible perfusion can be enabled, and that the insert 7 can be reversibly bent along an axis extending through the microporous carrier portion 3. Number and size of pores as well as pore density can be selected according to needs. Further, the pores may be randomly distributed or arranged in a geometrically ordered pattern. In the microporous carrier portion 3 shown in FIG. 8A, the pores are arranged in a geometrically ordered and symmetric pattern. Such pattern may be polygonal, for instance octagonal as shown, or have any other form including rectangular, circular or ellipsoid forms. According to an exemplary embodiment, a microporous carrier portion 3 as disclosed herein may comprise a multitude of pores, for example 8 to 200 pores, 12 to 150 pores, 16 to 100 pores or 20 to 80 pores. In this case, the pore mean diameter may preferably be relatively large, for instance, 100 μm to 1000 μm, 200 μm to 750 μm or250 μm to 500 μm. The pore density may be 8 to 200 pores/cm.sup.2, 12 to 150 pores/cm.sup.2, 16 to 100 pores/cm.sup.2 or 20 to 80 20 pores/cm.sup.2. As illustrated in FIG. 8B, the microporous carrier portion 3, according to another exemplary embodiment, comprises 20 to 1500 pores, 50 to 1000 pores or 100 to 750 pores. In this case, the pore mean diameter is preferably relatively small, for instance, 5 μm to 100 μm, 8 μm to 75 μm or 10 μm to 50 μm. The pore density may be 20 to 1500 pores/cm.sup.2, 50 to 1000 pores/cm.sup.2 or 100 to 750 pores/cm.sup.2. The pores can be conveniently produced by molding using appropriate matrices, or forming a mesh using conventional weaving techniques.

[0071] Referring to FIG. 9 it can be seen that fluidic devices 1 as disclosed herein are not limited insofar as they comprise only one flow chamber 2. Fluidic devices 1 as disclosed herein may rather comprise more than one flow chamber 2. For example, there may be a plurality of flow chambers, and a plurality of corresponding carrier portions 3, 3′, 3″ may be comprised in the insert 7 sandwiched between a bottom plate 5 and a cover plate 6 as disclosed herein. In the embodiment shown in FIG. 9, the flow chambers 2 are arranged in a pattern comprising 6 columns by 4 rows. A single bottom plate 5 and a single cover plate 6 extend over opposing surfaces of the insert 7 and thus seal the plurality of flow chambers 2a, 2b, 2c and flow channels 4. The cover plate 6 further comprises a plurality of ports 11 providing fluid access to the plurality of flow chambers 2a, 2b, 2c via flow channels 4.

[0072] Referring to FIGS. 10 and 11, results on stress-strain measurements on inserts 7 as disclosed herein are shown. FIG. 10 are measurements where the forces needed to push tweezers with a biological specimen between the incision 9 and leave the biological specimen behind were simulated. The forces needed to manipulate the opening and closing of the insert 7 were simulated on a Zwick Z010 stress bench by pushing a pen with rounded tip and having a diameter of 1.2 mm in thickness layer direction onto and through an incision 9 that was pre-cut in an insert 7. Following three individual measurements, the forces were determined to be in the order of 3 mN.

[0073] FIG. 11 are measurements where the forces needed to widen an opening defined by the incision 9 by pulling to an extent so that the widened opening is able to receive a biological specimen, for instance to a width of 1 mm, were simulated. The forces needed to manipulate the opening of the insert 7 were simulated on a Zwick Z010 stress bench by pulling opposite ends of the insert 7 away from each other in opposite directions. The insert 7 was made of silicone having a Shore A hardness of 40 (Wacker Elastosil 3040/40). The microporous carrier portion 3 of the insert 7 was 35 μm thick and the pore diameter was 200 μm. Following an exemplary measurement, the results of which are shown in FIG. 11, the forces for widening the opening to a width of 1 mm were determined to be in the order of 800 mN.

[0074] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the disclosure, and the appended claims.

[0075] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.

[0076] A single unit or device may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0077] Any reference signs in the claims should not be construed as limiting the scope.