Clip for holding microfluidic device

Abstract

A clip (1) for holding a microfluidic device (50) having a substantially planar bottom surface (51) and a substantially planar top surface (52), the clip comprising: a base (20) having a support surface (21) for supporting the bottom surface (51) of the microfluidic device (50); a cover plate (30) for holding the microfluidic device (50) on the support surface (21) of the base (20); a hinge (40) for connecting the cover plate (30) to the base (20) to rotate the cover plate (30) about a hinge axis (41); a pressure plate (31) mounted to the cover plate (30) for relative rotation about an axis of rotation (32) extending parallel to the hinge axis (41), the pressure plate (31) having an abutment surface (33) for engagement with a top surface (52) of the microfluidic device (50); and a clamping mechanism (61) for releasably securing the cover plate (30) to the base (20) for compressively holding the microfluidic device (50) between the support surface (21) and the abutment surface (33). The rotatable pressure plate (31) is pressed flush on the top surface (52) of the microfluidic device (50) such that the compression exerted by the clamp (61) on the microfluidic device (50) is more uniform.

Description

Technical Field

[0001] The present invention generally relates to a clip, and more particularly to a clip for holding a microfluidic device. Background Technology

[0002] Any discussion of prior art in the specification should not be construed as an admission that the prior art is widely known or constitutes common knowledge in the art.

[0003] Microfluidic devices are typically fabricated by bonding two or more layers of material together, with at least one layer including microfluidic features such as microchannels. These layers need to be bonded together sufficiently to prevent leakage between them.

[0004] Layers in microfluidic devices are typically permanently bonded together, for example, using plasma bonding techniques. However, plasma bonding is irreversible, and microfluidic devices manufactured using this process often exhibit leaks. Furthermore, plasma bonding techniques are generally expensive.

[0005] When holding layers of a microfluidic device together, mechanical clips can be used to compressively join the top and bottom layers separately. However, these mechanical clip systems are typically manufactured for use with microfluidic devices of a specific thickness and may not adequately hold microfluidic devices of varying thicknesses. Holding a microfluidic device that is thicker (or thinner) than intended for use with mechanical clips can lead to potential leaks, and the clips may be difficult or inconvenient to use.

[0006] The purpose of this invention is to overcome or improve at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0007] The object of certain embodiments of the present invention is to provide a clip for holding a microfluidic device that can easily accept microfluidic devices of different thicknesses and is relatively easy to use. Summary of the Invention

[0008] According to one aspect of the invention, a clip for holding a microfluidic device is provided, the microfluidic device having a generally planar bottom surface and a generally planar top surface, the clip comprising: A base with a support surface for supporting the bottom surface of a microfluidic device; A cover plate for holding the microfluidic device on the support surface of the base; A hinge that connects the cover plate to the base, allowing the cover plate to rotate about the hinge axis; A pressure plate, mounted to a cover plate for relative rotation about a rotation axis extending parallel to the hinge axis, the pressure plate having an abutment surface for engaging with the top surface of the microfluidic device; and A clamping mechanism is provided for releasably securing the cover plate to the base to compressively hold the microfluidic device between the support surface and the abutment surface.

[0009] Preferably, the abutment surface is generally planar and elongated, such that the axis of rotation is parallel to the longitudinal extension of the abutment surface.

[0010] The axis of rotation preferably bisects the width of the contact surface.

[0011] Preferably, the cover plate includes an outer frame for laterally surrounding the pressure plate, such that the pressure plate can rotate about a rotation axis within the outer frame.

[0012] Preferably, the clamping mechanism is adjustable to change the compression of the microfluidic device between the support surface and the abutment surface.

[0013] The clamping mechanism is preferably manually adjustable.

[0014] Preferably, the clamping mechanism has a clamp with an internal threaded hole and a manually rotatable threaded shaft with complementary external threads.

[0015] The threaded shaft preferably has a longitudinal axis and is mounted to allow for angular movement relative to the support surface of the base.

[0016] Preferably, the clamp is rotatably mounted to the base.

[0017] In some embodiments, the clamping mechanism has a helical shaft and a manually rotatable nut with complementary internal threads.

[0018] Preferably, the pressure plate has at least one hole for fluid connection with the microfluidic device.

[0019] The base preferably has an observation port for observing the microfluidic device.

[0020] Preferably, the observation aperture has a chamfered periphery to allow the lens of the inverted microscope with a truncated conical end structure to be positioned close to the bottom surface of the generally flat microfluidic device and close to the chamfered periphery of the observation aperture.

[0021] The support surface of the base is preferably configured to receive a standard microscope slide.

[0022] Preferably, the hinge includes a first complementary structural feature integrally formed on the base and the cover plate, respectively.

[0023] The first complementary structural feature is preferably a snap-fit ​​connection between the base and the cover.

[0024] Preferably, each of the outer frame and the pressure plate includes a corresponding integrally formed second complementary structural feature.

[0025] The second complementary structural feature is preferably a snap-fit ​​connection to connect the outer frame and the pressure plate.

[0026] Preferably, the base, outer frame, and pressure plate are all integral components.

[0027] The base, cover and / or pressure plate are preferably made of a polymer material that can be autoclaved.

[0028] Preferably, the base, cover, and / or pressure plate are formed of polypropylene or PEEK.

[0029] The base, cover, and / or pressure plate preferably include embedded reinforcing elements.

[0030] Preferably, the reinforcing element comprises a metal.

[0031] The clamping mechanism preferably provides at least one predetermined setting for applying a relevant level of compressive force to the microfluidic device.

[0032] Preferably, the clamping mechanism includes a force sensor for providing an output indicating at least one predetermined setting.

[0033] The clamping mechanism preferably includes an LED indicator that responds to the output from a force sensor.

[0034] In some embodiments, the clamping mechanism includes a piezoelectric element for providing an output indicating at least one predetermined setting. In other embodiments, the clamping mechanism includes a force gauge for providing an output indicating at least one predetermined setting.

[0035] Unless the context explicitly requires otherwise, the words “comprising” and “including” in the specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, they should be interpreted as “including but not limited to”. Attached Figure Description

[0036] Preferred embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings, wherein: Figure 1 This is a perspective view of a clip used to hold a microfluidic device in an open configuration; Figure 2 yes Figure 1 A perspective view of the card holder in a closed configuration; Figure 3 yes Figure 1 An exploded perspective view of the card holder; Figure 4 It is shown as being used with a microfluidic device of the first thickness. Figure 1 Side view of the card holder; Figure 5 It is shown as being used with a microfluidic device of a second thickness. Figure 1 Side view of the card holder; Figure 6 It is shown as being used with a microfluidic device of third thickness. Figure 1 A side view of the card holder; and Figure 7 This is shown as an inverted microscope for use with observing microfluidic devices through a hole in the base. Figure 1 A cross-sectional side view of the clip. Detailed Implementation

[0037] Figure 1 A clip 1 for holding a microfluidic device is shown. The clip 1 has a base 20 having a support surface 21 that supports the bottom surface of the microfluidic device; a cover plate 30 that holds the microfluidic device on the support surface 21 of the base 20; and a hinge 40 that connects the cover plate to the base to allow the cover plate to rotate about a hinge axis 41. A pressure plate 31 is mounted to the cover plate 30 to rotate relative to it about a rotation axis 32 extending parallel to the hinge axis 42. The pressure plate 31 has an abutment surface 33 for engaging with the top surface of the microfluidic device. Figures 4 to 6 As best shown, the microfluidic device 50 has a generally planar bottom surface 51 and a generally planar top surface 52. The clamping mechanism 60 is configured to releasably secure the cover plate 30 to the base 20, thereby compressively holding the microfluidic device between the support surface 21 and the abutment surface 32.

[0038] like Figures 1 to 3 As best shown, the abutment surface 33 of the pressure plate 31 is generally planar and elongated, wherein the axis of rotation 32 extends longitudinally along the pressure plate and bisects the width of the abutment surface, such that the axis of rotation 32 is parallel to the longitudinal extension of the abutment surface 33. The cover plate 30 includes a peripheral frame 34 that laterally surrounds the pressure plate, allowing the pressure plate to rotate within the peripheral frame. The peripheral frame 34 and the pressure plate 31 include complementary structural features in the form of a shaft 35 formed on the pressure plate 31 and a shaft receiving recess 36 formed on the inner surface 37 of the peripheral frame 34. The shaft 35 and the shaft receiving recess 36 are snap-fitted together to rotatably mount the pressure plate to the cover plate, thereby defining the axis of rotation 32.

[0039] like Figure 1 , Figure 2 and Figure 3As shown, the pressure plate 31 has at least one hole 67 for fluid connection with a microfluidic device. Conveniently, the pressure plate may have a series of identical holes 67 or different holes formed in predetermined locations within the pressure plate during the molding process. In other forms, the holes 67 may be formed after the pressure plate is manufactured. For example, the pressure plate 31 may include two drilled holes designed to align with corresponding inlet and outlet ports on the microfluidic device 50. These two drilled holes will then serve as inlet and outlet for microfluidic features (e.g., microfluidic channels) of the microfluidic device 50.

[0040] like Figure 3 As best shown, hinge 40 includes complementary structural features in the form of a clip structure 42 formed on base 20 and a corresponding shaft 43 formed on cover 30. Clip structure 42 and shaft 43 can be snapped together to hinge the base and cover, thereby defining hinge axis 41.

[0041] The clamping mechanism 60 includes a clamp 61 with an internally threaded hole 62 and a manually rotatable threaded shaft 63 with complementary external threads, allowing the clamping mechanism to be manually adjusted to change the compression of the microfluidic device between the support surface 21 and the abutment surface 33. The clamp 61 is rotatably mounted on the base, allowing the longitudinal axis 64 of the threaded shaft 63 to angularly move relative to the support surface 21 of the base. Figures 1 to 7 In the preferred embodiment shown, the clamping mechanism includes two internally threaded holes 62 and two threaded shafts 63. However, it should be understood that any desired number of threaded holes and threaded shafts can be used to meet the requirements of other embodiments of the clamp. In an alternative embodiment, the clamping mechanism may include an externally threaded shaft and a manually rotatable nut with complementary internal threads. Other mechanisms for applying clamping force to secure the cover to the base can be used, such as spring-loaded clamping mechanisms, rod-loaded clamping mechanisms, cam mechanisms, or toggle clamps.

[0042] like Figure 3 As best shown, the clamp 61 and the base 20 may include complementary structural features, in the form of a clamping structure 24 formed on the base 20 and a corresponding clamping shaft 66 formed on the clamp 61. The clamping structure 24 and the clamping shaft 66 can be snapped together to rotatably mount the clamp 61 on the base 20.

[0043] When holding the microfluidic device using clamp 1, place the planar bottom surface of the microfluidic device (e.g., the bottom surface of a microscope slide) on the support surface 21 of the base 20. Then, rotate the cover plate 30 relative to the base until the abutment surface 33 engages with the top surface of the microfluidic device. Next, rotate clamp 61 relative to the base until the longitudinal axis 64 of the threaded shaft 63 is substantially perpendicular to the top surface 52 of the microfluidic device 50. Then, rotate the threaded shaft 63 relative to the internal threaded hole 62, thereby moving the threaded shaft toward the outer frame 64 until the end 65 of the threaded shaft abuts a portion of the outer frame 64, thereby pressing the outer frame against the base and compressing the microfluidic device 50 between the support surface 21 and the abutment surface 33.

[0044] Compression between the support surface 21 and the abutment surface 33 laminates the microfluidic device 50 together, thereby forming a substantially leak-free microfluidic environment. For example, the bottom layer of the microfluidic device may be a microscope slide, while the top layer may be a layer of material including microfluidic features, such as microfluidic channels on one surface. Contact forces between the microscope slide and the surface including the microfluidic channels seal the microfluidic channels against the microscope slide, such that the microscope slide acts as a base for the microfluidic channels. Alternatively, the microfluidic device may include a first layer and a second layer, each layer including an inner surface having corresponding complementary microfluidic features, such that when the inner surfaces are pressed together, they define microfluidic channels.

[0045] After use, the threaded shaft 63 can be unscrewed from the internal threaded hole 62 until the end 65 of the threaded shaft separates from the outer frame, thereby releasing the compressive force on the microfluidic device and allowing the clamp 61 to rotate outward away from the cover plate 30. The cover plate 30 can then be rotated about the hinge axis 41 to move the abutment surface 33 of the pressure plate 31 to disengage from the top surface 52 of the microfluidic device 50. The microfluidic device can then be removed for further analysis and / or cleaning, facilitating the reuse of the microfluidic device 50 and the clamp 1. The reusability of the clamp and the microfluidic device significantly reduces waste and cost, providing a sustainable solution for microfluidic applications.

[0046] Reference Figures 4 to 6 It is understood that microfluidic devices 50 of varying thicknesses can be placed on the clip 1, and the pressure plate 31 can rotate relative to the outer frame, such that the abutment surface 33 engages with the top surface 52 in a substantially planar manner. For example, in Figure 4 In the diagram, clip 1 is shown as being used to hold a microfluidic device 50 of thickness X. The outer frame 34 is angled upward relative to the top surface 52 of the microfluidic device, but the pressure plate is angled relative to the outer frame, such that the abutment surface 33 engages the top surface in a substantially planar manner.

[0047] exist Figure 5In another example shown, the thickness Y of the microfluidic device is less than X. The outer frame 34 is angled downward relative to the top surface 52 of the microfluidic device, but the pressure plate is also angled relative to the outer frame, thereby allowing the abutment surface 33 to engage the top surface 52 in a substantially planar manner.

[0048] exist Figure 6 In another example shown, the thickness Z of the microfluidic device is less than X but greater than Y. The outer frame 34 is angled only slightly downward relative to the top surface 52 of the microfluidic device, so that the pressure plate is also angled only slightly relative to the outer frame. This also results in the abutment surface 33 engaging the top surface 52 in a substantially planar manner.

[0049] Because the abutment surfaces are joined to the top surface in a substantially planar manner, the pressure applied to the top surface 52 is substantially uniform above the top surface. Advantageously, this reduces the likelihood of leakage between layers of the microfluidic device (e.g., at the interface between the top surface of a microscope slide and the bottom surface of another layer of the microfluidic device). Therefore, the device can be easily adapted to microfluidic devices of varying thicknesses.

[0050] Reference Figure 7 The base 20 has an observation port 22 for observing the microfluidic device. The support surface 21 of the base is configured to receive a standard 75 mm × 25 mm microscope slide, and the observation port is large enough to allow observation of the standard microscope slide. In use, the microscope slide is pressed against the bottom surface of the layer of the microfluidic device 50 and serves as a base for the flow channel of the microfluidic device, thereby allowing the user to observe the flow channel. Advantageously, the observation port may have a chamfered periphery 23 to allow the lens of the inverted microscope 70, which has a truncated conical end structure 71, to be positioned close to the bottom surface of the generally planar surface of the microfluidic device and close to the chamfered periphery of the observation port.

[0051] The base 20, outer frame 34, and pressure plate 31 can be a single, integral component, preferably made of a durable and chemically resistant plastic material. In a preferred embodiment, the base, cover, and pressure plate are integrally formed from an autoclaved polymer material (e.g., polypropylene or PEEK).

[0052] The base, cover, and / or pressure plate may include embedded reinforcing elements. For example, when needed, a metal element may be embedded in any of the base, cover, and / or pressure plate to provide additional mechanical strength.

[0053] The clamping mechanism may provide at least one predetermined setting for applying a relevant level of compressive force to the microfluidic device. For example, the clamping mechanism may include a force sensor for providing an output indicating at least one predetermined setting. The force sensor may be an electronic force sensor associated with the operability of an indicator (e.g., an LED) that responds to the output from the force sensor, allowing a user to observe whether the predetermined setting of compressive force has been reached.

[0054] Alternatively, the clamping mechanism may include a force gauge for providing an output indicating at least one predetermined setting. The force gauge may be miniaturized to be embedded in another element of the clamp 61 or clip 1 (e.g., base 20 or cover 30). The force gauge may include a dial to allow the user to observe whether the predetermined setting of the compressive force has been reached.

[0055] In other embodiments, the clamping mechanism may include a piezoelectric element for providing an output indicating a predetermined setting. For example, the piezoelectric element may be located at, for example, clamp 61, and respond to stress and / or strain generated in clamp 61 due to a force applied to cover plate 30. The clamping mechanism may also include an indicator (e.g., an LED) that responds to the output from the piezoelectric element, allowing a user to observe whether a predetermined setting of compressive force has been reached.

[0056] Although the invention has been described with reference to specific examples, those skilled in the art will understand that the invention can also take many other forms.

Claims

1. A clip for holding a microfluidic device, the microfluidic device having a generally planar bottom surface and a generally planar top surface, the clip comprising: A base having a support surface for supporting the bottom surface of the microfluidic device; A cover plate for holding the microfluidic device on the support surface of the base; A hinge that connects the cover plate to the base, allowing the cover plate to rotate about the hinge axis; A pressure plate, which is mounted to the cover plate and is rotatable relative to the cover plate about a rotation axis extending parallel to the hinge axis, the pressure plate having an abutment surface for engaging with the top surface of the microfluidic device; as well as A clamping mechanism is provided for releasably securing the cover plate to the base to compressively hold the microfluidic device between the support surface and the abutment surface.

2. The card holder according to claim 1, wherein, The abutment surface is generally planar and elongated, such that the axis of rotation is parallel to the longitudinal extension of the abutment surface.

3. The card holder according to claim 2, wherein, The axis of rotation essentially bisects the width of the abutment surface.

4. The card holder according to any of the preceding claims, wherein, The cover plate includes an outer frame for laterally surrounding the pressure plate, allowing the pressure plate to rotate about the axis of rotation within the outer frame.

5. The card holder according to any one of the preceding claims, wherein, The clamping mechanism is adjustable to change the compression of the microfluidic device between the support surface and the abutment surface.

6. The card holder according to claim 5, wherein, The clamping mechanism can be manually adjusted.

7. The card holder according to claim 6, wherein, The clamping mechanism has a clamp with an internal threaded hole and a manually rotatable threaded shaft with complementary external threads.

8. The card holder according to claim 7, wherein, The threaded shaft has a longitudinal axis and is mounted to allow for angular movement relative to the support surface of the base.

9. The card holder according to claim 7 or 8, wherein, The clamp can be rotatably mounted to the base.

10. The card holder according to any of the preceding claims, wherein, The pressure plate has at least one hole for fluid connection with the microfluidic device.

11. The card holder according to any of the preceding claims, wherein, The base has an observation port for observing the microfluidic device.

12. The card holder according to claim 11, wherein, The observation aperture has a chamfered perimeter to allow the lens of the inverted microscope, which has a truncated conical end structure, to be positioned close to the bottom surface of the generally flat surface of the microfluidic device and close to the chamfered perimeter of the observation aperture.

13. The card holder according to any of the preceding claims, wherein, The base's support surface is configured to receive a standard microscope slide.

14. The card holder according to any of the preceding claims, wherein, The hinge includes a first complementary structural feature integrally formed on the base and the cover plate, respectively.

15. The card holder according to claim 14, wherein, The first complementary structural feature snaps together to connect the base and the cover.

16. The card holder according to any of the preceding claims, wherein, Each of the outer frame and the pressure plate includes a corresponding integrally formed second complementary structural feature.

17. The card holder according to claim 16, wherein, The second complementary structural feature snaps together to connect the outer frame and the pressure plate.

18. The card holder according to any of the preceding claims, wherein, The base, the cover plate, and the pressure plate are all integral components.

19. The card holder according to any of the preceding claims, wherein, The base, the cover, and / or the pressure plate are formed of a polymer material capable of being autoclaved.

20. The card holder according to any of the preceding claims, wherein, The base, the cover plate, and / or the pressure plate are formed of polypropylene or PEEK.

21. The card holder according to any of the preceding claims, wherein, The base, the cover plate, and / or the pressure plate include embedded reinforcement elements.

22. The card holder according to claim 21, wherein, The reinforcing element comprises metal.

23. The card holder according to any of the preceding claims, wherein, The clamping mechanism provides at least one predetermined setting for applying a relevant level of compressive force to the microfluidic device.

24. The card holder according to claim 23, wherein, The clamping mechanism includes a force sensor for providing an output indicating the at least one predetermined setting.

25. The card holder according to claim 24, wherein, The clamping mechanism includes an LED indicator that responds to the output from the force sensor.

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