FR3090614A1 - MICROFLUIDIC CHIP CONNECTION SYSTEM - Google Patents

Abstract

The present invention relates to a microfluidic system, comprising a microfluidic chip having a microfluidic channel, a first face, the first face having an entrance of the microfluidic channel, the chip comprising a part forming a seal disposed at the level of the first face around the entrance , a support having a pipe passing through the support, a second face, the second face having an orifice in the pipe characterized in that during the passage from a disconnected configuration to a connected configuration, the part forming the seal is deformed by the second face so as to form between the first face and the second face a fluid-tight connection fluidly connecting the pipe and the microfluidic channel. Figure for the abstract: Fig. 1

Description

Description

Title of the invention: MICROFLUIDIC CHIP CONNECTION SYSTEM

Technical area

The present invention relates to microfluidic connectors, and more particularly a microfluidic chip connection system and a microfluidic chip adapted to such a system.

Prior art

[0002] A microfluidic chip can be connected to a reservoir of fluid, more particularly of liquid. A connecting tube generally connects the chip to the reservoir. The connecting tube and the microfluidic chip are tightly connected so as to control the quantity of fluid introduced into the chip and to avoid fluid losses.

The microfluidic chip can be produced, in a known manner, from elastomeric material, such as polydimethylsiloxane (PDMS), and from glass. Such a chip can be manufactured by molding one face of a layer of PDMS and by bonding this face to one face of a glass slide, so as to form one or more microfluidic channels at the interface between the layer of PDMS and the glass slide.

[0004] Prior to bonding the PDMS layer and the glass slide, a hole can be machined through the thickness of the PDMS layer. It is thus possible to introduce the connection tube into the hole, for example having a diameter slightly smaller than the external diameter of the connection tube, so as to ensure a fluid-tight connection between the connection tube and the microfluidic chip.

Alternatively or in addition, it is known to introduce the connecting tube into the hole, then to make a tight seal by depositing glue between the tube and the microfluidic chip.

This type of sealed connection between the tube and the microfluidic chip requires precise handling. It also requires repeating the insertion of the tube and the bonding when the chip includes several holes, corresponding to several fluidic inputs of the chip. The use of glue can also make this type of connection expensive. Finally, this type of connection does not meet a standard relating to the connection of microfluidic chips, necessary for the industrial development of the technological field in question. The need for such standards is for example described in the publication by van Heeren (van Heeren, H., 2012, Standards for connecting microfluidic devices?, Lab on a Chip, 12 (6), 1022-1025).

For this purpose, the "PDMS Chip interface" system of the company Dolomite Center Ltd has for example been developed. This system includes a microfluidic chip. The chip includes a layer of PDMS and a glass slide, through which a hole is machined so as to connect the microchannels with the outside of the chip. This system also includes a base, adapted to support the microfluidic chip, as well as a connector. The microfluidic chip is inserted into the base so as to present the glass slide comprising the hole on its upper part. The connector comprises a main body and an integral joining part. A pipe is formed through the main body and the contiguous part so as to allow the insertion of a tube into the connector. The contiguous part of the connector is brought into contact with the glass slide, so as to bring the tube and the hole opposite, and thus to form a sealed connection between the tube and the microfluidic chip. Thus, it is possible to avoid the use of glue to make the connection. This connection also makes it possible to connect and disconnect the microfluidic chip on contract. However, this system requires machining the glass of the microfluidic chip so as to form a hole. In addition, the manufacture of the connector comprising a main body and an integral joining part can prove to be expensive.

Statement of the invention

An object of the invention is to provide a solution for manufacturing a system for connecting a microfluidic chip to a simpler tube than the systems of the prior art.

This object is achieved in the context of the present invention thanks to a microfluidic system, comprising:

- a microfluidic chip presenting:

a microfluidic channel, a first face, the first face having an entrance to the microfluidic channel, the chip comprising a part forming a seal placed at the level of the first face around the entrance,

- a support presenting:

a pipe passing through the support, a second face, the second face having an orifice in the pipe, characterized in that when passing from a disconnected configuration to a connected configuration of the system, the part forming a joint is deformed by the second face of so as to form between the first face and the second face a tight connection to the fluid fluidly connecting the pipe and the microfluidic channel.

As the chip has a part forming a seal arranged around the entrance to the microfluidic channel, it is possible to avoid the manufacture of a support comprising a contiguous part. It is also possible to directly connect the support to the entry of the microfluidic channel of the chip and thus to avoid the machining of the chip so as to form for example a hole in a glass slide.

The invention is advantageously supplemented by the following characteristics, taken individually or in any of their technically possible combinations:

- The part forming the joint is made of a first material having a first modulus of elasticity, and the support is made of a second material having a second modulus of elasticity, the first modulus of elasticity being strictly less than the second modulus of elasticity,

- the support has a third face on which the chip comes to rest when switching from the disconnected configuration to the connected configuration,

the orifice is surrounded by a raised projection on the second face, the shape of the projection being adapted to surround the entry in the connected configuration,

- the chip is entirely made of first material,

the chip comprises two superimposed layers made of the first material and bonded together so as to form the channel,

the chip is also made of a third material, the third material having a third modulus of elasticity strictly greater than the first modulus of elasticity, the third material being preferably chosen from a copolymer of cyclic olefin, polymethyl methacrylate, polystyrene, polycarbonate and polyethylene glycol diacrylate,

the first modulus of elasticity is between 50 kPa and 100 MPa, in particular between 200 kPa and 10 MPa, and preferably between 500 kPa and 3 MPa,

- the second modulus of elasticity is greater than 500 MPa, in particular greater than 1 GPa and preferably greater than 3 GPa,

the support comprises a mobile part and a main part, the mobile part having the second face, and the support comprises a means for separating the mobile part and the main part,

the support comprises a mobile part and a main part, the mobile part having the third face, and the support comprises a means of spacing the mobile part and the main part,

- the second face and the third face are flat and parallel.

Another object of the invention is a microfluidic chip, having a microfluidic channel, a first face, the first face having an inlet of the microfluidic channel, the chip comprising a part forming a seal made of a first material and disposed at the level of the first face around the entry, the chip also being made of a third material different from the first material.

Advantageously, the seal forming part of the chip is made of a first material having a first elasticity module, the third material has a third elasticity module, and the first elasticity module being strictly less than the third module of elasticity.

Brief description of the drawings

Other characteristics, aims and advantages of the invention will emerge from the description which follows, which is purely illustrative and not limiting, and which should be read with reference to the appended drawings in which:

[Fig.l]

Figure 1 schematically illustrates a system according to a first embodiment of the invention.

[Fig.2]

FIG. 2 schematically illustrates the tubes inserted in the support.

[Fig.3]

FIG. 3 schematically illustrates part of the support and the microfluidic chip in a connected configuration.

[Fig.4]

Figure 4 schematically illustrates a liquid tight connection between the support and the microfluidic chip.

[Fig.5]

FIG. 5 schematically illustrates a chip comprising two superimposed layers made of the first material.

[Fig.6]

FIG. 6 schematically illustrates part of a chip made of first material and third material, comprising a part forming a seal around each of the inputs of the microfluidic channels.

In all of the figures, similar elements bear identical references. DEFINITIONS

The term "microfluidic channel" means a channel one of the dimensions of a section of the channel of which is between 100 nm and 1 mm and preferably between 1 pm and 500 pm.

The term "height" of a channel means the minimum dimension of a section of the channel, and the term "width" of a channel means the maximum dimension of a section of the channel. Description of the embodiments

Referring to Figure 1, the system 1 comprises a microfluidic chip 2. The chip 2 has at least one microfluidic channel 3 and a first face 4 having an inlet 5 of the microfluidic channel 3. Preferably, the microfluidic chip 2 comprises a plurality of microfluidic channels 3, each microfluidic channel 3 having an inlet 5. The inlet 5 of the microfluidic channel has a height of less than 2000 μm, in particular less than 1500 μm and preferably less than 300 μm . Thus, it is not necessary to machine a fluid connection between the microfluidic channel 3 and the outside of the chip, the microfluidic input 5 being manufactured by the same microfabrication techniques as the microfluidic channel (s) 3. The chip 2 can be of generally parallelepiped shape and can have lateral faces, an upper face and a lower face. The lateral faces of the chip 2 correspond to the faces comprising the thickness of the chip 2, that is to say its minimum dimension. Preferably, the first face 4 is a lateral face of the chip 2. Thus, it is possible to observe, by imaging for example, the interior of the microfluidic channel or channels 3 through the upper or lower face, without the quality of the imagery is deteriorated or prevented by the connection of the chip 2.

The chip 2 comprises a part forming a seal 17. The part forming a seal 17 is disposed at the level of the first face 4, and around the or each of the inlets 5. The part forming a seal 17 is integral with the rest of the chip 2. The first face 4 comprises a face of the part forming a seal 17. Preferably, the part forming a seal 17 can correspond to the assembly of the chip 2. Thus, it is possible to simplify the manufacture of the chip by carrying out the chip 2 with a single material.

Referring to Figure 1 and Figure 2, the system 1 also includes a support 6. The support 6 has a second face 7, intended to come into contact with the first face 4 of the chip 2. The support 6 comprises at least one pipe 9, opening, at one of its ends, to an orifice 8 of the second face 7. Preferably, the orifice 8 is opposite the inlet 5, and in particular aligned with the inlet 5. The pipe 9 has at least one other end, opening onto another face of the support 6. The pipe 9 thus crosses the support 6. The pipe 9 can allow a flow of liquid to the orifice 8. Preferably, as illustrated in FIG. 2, a tube 10 can be introduced into the pipe 9. The tube 10 can be connected to the pipe 9 by a tight fluid connection (or fluid connection). Thus, it is possible to convey a liquid from a reservoir fluidly connected to the tube 10, to the orifice 8. The support 6 may have a plurality of parallel conduits 9, each opening onto an orifice 8 on the second surface 7 FIGS. 1, 2 and 3 illustrate for example a support comprising four fluidly parallel pipes 9, each opening onto an orifice 8 different from the second face 7.

The system 1 has a connected configuration and a disconnected configuration. In a disconnected configuration, the support 6 is configured to receive the chip 2 so that the input (s) 5 of the channel (s) 3 are facing the orifice (s) 8. The first face 4 of the chip 2 is then in look of the second face 7 of the support.

When switching from the disconnected configuration to a connected configuration of the system 1, the seal portion 17 is deformed by the second face 7 so as to form between the first face 4 and the second face 7, a fluid-tight connection fluidly connecting line 9 and microfluidic channel 3.

Preferably, the support 6 comprises a main part 15 and a movable part 14. The main part 15 is intended to be supported on the ground or on a fixed support. The support 6 comprises a means of spacing 16 of the movable part 14 relative to the main part 15. The spacing means 16 can for example be chosen at least from a screw, a lever, a spring, a gear, the gravity of the fixed or mobile part, a jack, a compressed air system, a latch and a rack. The spacer can be motorized. The spacer 16 allows the passage from the disconnected configuration to the connected configuration and vice versa.

The support 6 may also have a third face 11. When switching from the disconnected configuration to the connected configuration, the chip can come to bear on the third face 11. Thus, the deformation of the first face 4 by the second face 7 is facilitated.

The movable part 14 may have the second face 7. Thus, when the chip 2 is inserted in the support 6, the movement of the movable part 14 driven by the spacer 16 allows to bring the second face 7 in contact with the first face 4, and thus deform the first face 4 so as to form between the first face 4 and the second face 7 a fluid-tight connection fluidly connecting the pipe 9 and the microfluidic channel 3. In this embodiment, the main part 15 can have the third face 11.

The movable part 14 may also have the third face 11. Thus, when the chip 2 is inserted in the support 6, the movement of the movable part 14 driven by the spacer means 16 allows the chip 2 to be pushed so as to bring the first face 4 into contact with the second face 7, and thus to deform the first face 4 so as to form between the first face 4 and the second face 7 a fluid-tight connection fluidly connecting the pipe 9 and the channel 3 microfluidics. In this embodiment, the main part 15 can have the second face 7.

In another embodiment, the support 6 can have several mobile parts 14. A mobile part 14 can have the second face 7, and another mobile part 14 can have the third face 11. Thus, the movement of the chip when switching between the disconnected configuration and the connected configuration can be limited.

Preferably, the second face 7 and the third face 11 are generally planar and parallel to each other. Thus, the movement of the second face 7 and / or of the third face 11 during the transition from the disconnected configuration to the connected configuration makes it possible to avoid parasitic movements of the chip 2, preferably to block it, and thus to facilitate a alignment between orifice 8 and inlet 5.

Figure 4 illustrates a deformation of the seal portion 17 of the chip 2 in the connected configuration of the system 1. In one embodiment of the invention, the deformation of the seal portion 17 may be an elastic deformation . The part forming a seal 17 can be made of a first material having a first modulus of elasticity, and the support 6 made of a second material having a second modulus of elasticity, the first modulus of elasticity being strictly less than the second module d 'elasticity. Thus, during the transition from the connected configuration to the connected configuration, the part forming a seal 17 is elastically deformed and a sealed connection can be formed between the pipe 9 and the channel 3. Preferably, the first modulus of elasticity is between 50 kPa and 100 MPa, especially between 200 kPa and 10 MPa, and preferably between 500 kPa is 3 MPa. The first material can be at least chosen from PDMS, an elastomer, a plastic material, a material of plant origin, a metal, rubber, silicone and wax. Preferably, the second modulus of elasticity is greater than 500 MPa, in particular greater than 1 GPa and preferably greater than 3 GPa. The second material can be chosen from metal, a cyclic olefin copolymer, polymethyl methacrylate, polystyrene, polycarbonate, polyethylene glycol diacrylate, polylactic acid, acrylonitrile butadiene styrene, polyamide, crosslinked resin, steel and combinations thereof. Preferably, the support 6 can be manufactured by an additive manufacturing method (three-dimensional printing). Thus, the support can be adapted to the geometry of the chip 2 used in the system.

According to a different embodiment and compatible with the previous embodiment, the deformation of the seal portion 17 may be a plastic deformation. During the transition from the disconnected configuration to the connected configuration, the second face 7 can plastically deform the seal part 17 on the first surface 4. In this configuration mode, the seal part 17 does not return to its initial shape during transition from the connected configuration to the disconnected configuration of the system 1. Thus, it is possible to ensure a single use of a chip 2 during industrial use so as to avoid, for example, biological contamination of the chip 2 or artefacts driven by previous uses of the chip 2. The joint portion 17 can be formed by a hollow metal bead surrounding each entry 5.

The orifice 8 of the second face 7 is preferably surrounded by a projection 12 in relief of the second face 7 in the connected configuration. The shape of the projection 12 is adapted to surround the inlet 5 in the connected configuration. By "surround" is meant completely surround, or surround so that the projection extends angularly over more than 90% of the turn of the inlet 5. Thus, the tightness of the connection between the pipe 9 and the channel 5 can be reinforced. The projection 12 can have several shapes on the second face 4. FIG. 3 illustrates for example circular protrusions 12 sinking into the joint forming part 17 of the chip 2.

The support 6 may include a sealed connection between the tube 10 and the pipe 9. This sealed connection can be implemented by means of a sleeve, a ferrule and / or one or more seals.

Figure 5 illustrates a chip 2. The chip 2 can be made entirely of first material. Thus, the seal portion 17 is manufactured at the same time as the rest of the chip 2, and the manufacture of the chip 2 is simplified. The chip 2 can comprise two superimposed layers 13 made of first material and glued together so as to form the channel 3. The chip 2 can for example comprise two layers 13 made of PDMS. One of the layers 13 can be molded or micro-machined so as to present on one of its faces part of the channel or channels 3. The two layers 13 can be superimposed and glued so as to form the channel or channels 3 at the interface of the two layers 13. In one embodiment, the molding of the face of the layer of first material is configured so that the channel or channels 3 open onto an edge of said face. Thus, during the superposition of the two layers 13, the inlet (s) 5 are formed on a lateral face of the superposition of the layers 13. In another embodiment, compatible with the previous embodiment, it is possible to cut an edge of the superposition of layers 13 at the level of the channel (s) 3 to form the inlet (s) 5.

Figure 6 illustrates a chip 2 according to one aspect of the invention. The chip 2 comprises a part forming a seal 17 made of a first material, placed at the level of the first face 4 around the inlet 5, the chip 2 also being made of a third material different from the first material. Thus, the channel or channels of the chip 2 can be formed by a material resistant to solvents causing the swelling or the dissolution of the first material, while allowing the joint part 17 to deform during the transition to a connected configuration of the system 1.

The third material is preferably chosen from a copolymer of cyclic olefin, polymethyl methacrylate, polystyrene, polycarbonate and polyethylene glycol diacrylate. Thus, the channel (s) can chemically resist solvents such as silicone, alcohols, natural or artificial oils, and / or solutions comprising micro or nanoparticles and / or capsules.

The first material can be adapted to be deformed in an elastic and / or plastic manner. Preferably, the joint forming part is made of a first material having a first modulus of elasticity, and the third material has a third modulus of elasticity, the first modulus of elasticity being strictly less than the third modulus of elasticity. Thus, the seal portion is adapted to be deformed elastically.

Claims (1)

Claims [Claim 1] Microfluidic system (1), comprising: - a microfluidic chip (2) having: a microfluidic channel (3), a first face (4), the first face (4) having an inlet (5) of the microfluidic channel (3), the chip comprising a seal-forming part (17) disposed at the level of the first face (4) around the entry (5), - a support (6) having: a pipe (9) passing through the support (6), a second face (7), the second face (7) having an orifice (8) in the pipe (9), characterized in that when switching from a disconnected configuration to a connected configuration of the system (1), the seal part (17) is deformed by the second face (7) so as to form between the first face (4) and the second face (7) a fluid tight connection fluidly connecting the pipe (9) and the microfluidic channel (3). [Claim 2] A microfluidic system (1) according to claim 1, in which: - the joint part (17) is made of a first material having a first modulus of elasticity, - the support (6) is made of a second material having a second modulus of elasticity, the first modulus of elasticity being strictly less than the second modulus of elasticity. [Claim 3] System (1) according to claim 1 or 2, in which the support (6) has a third face (11) on which the chip (2) comes to bear when passing from the disconnected configuration to the connected configuration. [Claim 4] System (1) according to one of claims 1 to 3, in which the orifice (8) is surrounded by a projection (12) in relief from the second face (7), the shape of the projection (12) being adapted to surround the entry (5) in the connected configuration. [Claim 5] System (1) according to one of claims 1 to 4, in which the chip (2) is entirely made of first material. [Claim 6] System (1) according to claim 5, in which the chip (2) comprises two superposed layers (13) made of the first material and glued together so as to form the channel (3). [Claim 7] System (1) according to one of claims 1 to 4 or 6, in which the chip (2) is also made of a third material, the third material having a third modulus of elasticity strictly greater than the first modulus of elasticity, the third material being preferably chosen from a copolymer of cyclic olefin, polymethyl methacrylate, polystyrene, polycarbonate and polyethylene glycol diacrylate. [Claim 8] System (1) according to one of claims 2 to 7, in which the first modulus of elasticity is between 50 kPa and 100 MPa, in particular between 200 kPa and 10 MPa, and preferably between 500 kPa and 3 MPa. [Claim 9] System (1) according to one of claims 2 to 8, in which the second modulus of elasticity is greater than 500 MPa, in particular greater than 1 GPa and preferably greater than 3 GPa. [Claim 10] System (1) according to one of claims 1 to 9, in which the support comprises a movable part (14) and a main part (15), the movable part (14) having the second face (7), and in which the support (6) comprises a means for separating (16) the movable part (14) and the main part (15). [Claim 11] System (1) according to one of claims 3 to 10, in which the support (6) comprises a mobile part (14) and a main part (15), the mobile part having the third face (11), and in which the support (6) comprises a means for separating (16) the movable part (14) and the main part (15). [Claim 12] System (1) according to one of Claims 3 to 11, in which the second face (7) and the third face (11) are plane and parallel. [Claim 13] Microfluidic chip, having: a microfluidic channel (3), a first face (4), the first face (4) having an inlet (5) of the microfluidic channel (3), the chip comprising a seal part (17) made in a first material, disposed at the first face (4) around the inlet (5), the chip also being made of a third material different from the first material. [Claim 14] Microfluidic chip according to claim 13, in which the seal part is made of a first material having a first modulus of elasticity, and in which the third material has a third modulus of elasticity, the first modulus of elasticity being strictly lower than the third modulus of elasticity.