CN213890909U

CN213890909U - Polydimethylsiloxane micro-fluidic chip preparation die

Info

Publication number: CN213890909U
Application number: CN202022462979.8U
Authority: CN
Inventors: 王晓冬
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-10-29
Filing date: 2020-10-29
Publication date: 2021-08-06
Anticipated expiration: 2030-10-29

Abstract

The embodiment of the utility model discloses polydimethylsiloxane micro-fluidic chip preparation mould, the preparation mould includes: the bottom plate is provided with a groove, the bottom of the groove is provided with a plurality of exhaust holes, the structural template is embedded into the lower containing cavity, the forming frame is placed into the upper containing cavity, the pressing cover is pressed on the bottom plate, and the middle of the pressing cover is hollowed to form a polydimethylsiloxane prepolymer adding hole. In the preparation of the polydimethylsiloxane micro-fluidic chip, the requirement on the sample adding accuracy of the PDMS prepolymer before PDMS curing is low. The liquid level of the added PDMS prepolymer liquid is not higher than the highest point of the molding frame, and the height of the prepared microfluidic chip is the height of the molding frame, so that the thickness of the microfluidic chip can be conveniently controlled in preparation. The PDMS does not need to be cut after being solidified; the prepared polydimethylsiloxane micro-fluidic chip has accurate appearance three-dimensional size and high batch-to-batch uniformity.

Description

Polydimethylsiloxane micro-fluidic chip preparation die

Technical Field

The utility model relates to a micro-fluidic chip preparation technical field, concretely relates to polydimethylsiloxane micro-fluidic chip preparation mould.

Background

Polydimethylsiloxane (PDMS) is a high molecular silicone material, and is transparent. The material is prepared by mixing dimethyl siloxane as a monomer before polymerization with a hardening agent and then curing the mixture at a certain temperature for a certain time. The mixing of the dimethylsiloxane with the hardener (PDMS prepolymer) generates a large amount of bubbles, which need to be evacuated to float to the surface of the liquid and break, thereby completely removing the bubbles, which may last for more than 30 minutes. After the bubbles are removed, the mixture is placed into an oven to be heated, and the heating temperature is generally different from 40 ℃ to 120 ℃. Different heating temperatures and times will produce PDMS with different hardness.

The micro-fluidic chip made of the PDMS material has the advantages of easy processing and low cost, and the material has good chemical inertness and biocompatibility and can be bonded with various materials at room temperature. Because PDMS and the silicon chip have good adhesiveness, a microstructure can be formed on the silicon chip through an MEMS process and is transferred to a PDMS material through pouring to prepare the PDMS microfluidic chip. Namely, the PDMS prepolymer is poured on a silicon chip and waits for the completion of curing, and the micro structure on the cured silicon chip is transferred on PDMS. By this method, a PDMS microfluidic chip having a minute structural element can be manufactured at low cost. And (4) taking off the cured PDMS from the silicon wafer, and further cutting to form. Since PDMS has high elasticity in structure due to low young's modulus, stable and precise cutting of PDMS is difficult to achieve. Secondly, due to the high viscosity of the PDMS prepolymer, it is difficult to accurately pour a certain amount of PDMS onto a silicon wafer, resulting in a variation in the thickness between batches of PDMS produced.

SUMMERY OF THE UTILITY MODEL

An object of the embodiment of the utility model is to provide a polydimethylsiloxane micro-fluidic chip preparation mould for there is technical problem such as difference in the PDMS batch thickness that is difficult to realize stable accurate cutting, the production of PDMS in solving present micro-fluidic chip preparation.

In order to realize the utility model discloses a purpose, the utility model discloses the technical scheme who adopts does:

the utility model provides a polydimethylsiloxane micro-fluidic chip preparation mould, the preparation mould includes: bottom plate, structural template, shaping frame and gland, set up the recess on the bottom plate, the recess bottom is provided with a plurality of exhaust holes, the recess includes: the structure template is embedded into the lower accommodating cavity, the forming frame is placed into the upper accommodating cavity, the gland is pressed on the bottom plate, and the middle of the gland is hollowed to form a polydimethylsiloxane prepolymer adding hole.

Preferably, the lower accommodating cavity is larger than the upper accommodating cavity, and a position where the lower accommodating cavity is connected with the upper accommodating cavity forms a limiting step.

Preferably, the bottom plate is a metal bottom plate, and a plurality of press-fitting limiting holes are formed around the groove.

Further, the structure template is a silicon wafer formed by accurate cutting, and the upper surface of the silicon wafer is provided with a microstructure.

Preferably, the lower surface of the structural formwork is tightly bonded to the bottom of the groove using an adhesive.

Preferably, the forming frame comprises a side wall integrally formed using a plastic material and an outwardly extending upper edge.

Preferably, a plurality of packaging limiting holes are formed in the side wall of one side of the forming frame.

Furthermore, the gland is a metal gland, a plurality of fixing columns are arranged below the gland around the polydimethylsiloxane prepolymer adding hole, and the fixing columns are inserted into the bottom plate to realize limiting and fixing during assembly.

Preferably, the opposite side of the gland is provided with an internal recess.

Preferably, the bottom plate, the forming frame and the gland are provided with tangent planes at corner positions in the same direction.

The utility model also provides a polydimethylsiloxane micro-fluidic chip preparation method, preparation method includes: before the first use, the structural template is embedded into the groove of the bottom plate; placing a forming frame into the groove, pressing a pressing cover on the bottom plate, pressing the forming frame tightly, and enclosing a polydimethylsiloxane prepolymer accommodating cavity by the structural template and the forming frame; filling a polydimethylsiloxane prepolymer into a hole formed by hollowing the middle of the gland, and pouring a preset amount of polydimethylsiloxane prepolymer; putting the whole die containing the prepolymer into a closed container, and vacuumizing until no bubbles are generated; transferring the whole mould into heating equipment under a vacuum condition for heating until the liquid is completely solidified; and integrally taking out the mold, taking down the gland, slowly and uniformly taking out the forming frame, and ensuring that the solidified polydimethylsiloxane is taken out along with the forming frame to obtain the polydimethylsiloxane microfluidic chip taking the forming frame as an outer frame.

Preferably, the side wall of the forming frame is closely attached to the inner surface of the groove, the upper edge of the forming frame is assembled with the assembling portion of the pressing cover, and the pressing cover presses the forming frame through the upper edge.

Preferably, the structural formwork is tightly bonded to the groove bottom by an adhesive, which comprises: paving a layer of bonding layer at the bottom of the groove of the bottom plate by using an adhesive; and placing the structural template on the bonding layer and applying a force downwards, wherein the gas in the bonding layer is exhausted from a plurality of exhaust holes, and the redundant adhesive enters the exhaust holes, and the structural template is flatly laid at the bottom of the groove.

Preferably, the adhesive is a polydimethylsiloxane adhesive.

Preferably, the liquid level of the polydimethylsiloxane prepolymer is not higher than the upper surface of the forming frame.

Compared with the prior art, the embodiment of the utility model provides an in preparation polydimethylsiloxane micro-fluidic chip, it is low to PDMS prepolymer application of sample volume precision requirement before the PDMS solidification. The liquid level of the added PDMS prepolymer liquid is not higher than the highest point of the molding frame, and the height of the prepared microfluidic chip is the height of the molding frame, so that the thickness of the microfluidic chip can be conveniently controlled in preparation. The PDMS does not need to be cut after being solidified; the prepared polydimethylsiloxane micro-fluidic chip has accurate appearance three-dimensional size and high batch-to-batch uniformity.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. Some specific embodiments of the present application will be described in detail hereinafter by way of illustration and not limitation with reference to the accompanying drawings. The same reference numbers will be used throughout the drawings to refer to the same or like parts or portions, and it will be understood by those skilled in the art that the drawings are not necessarily drawn to scale, in which:

fig. 1 is a schematic diagram of an assembly structure of a polydimethylsiloxane micro-fluidic chip preparation mold disclosed in the present invention;

fig. 2 is a schematic structural diagram of a polydimethylsiloxane micro-fluidic chip preparation mold disclosed in the present invention;

fig. 3 is a sectional view of the structure of a mold for preparing a polydimethylsiloxane micro-fluidic chip of the present invention.

In the above drawings:

1. a base plate; 11. a groove; 12. an exhaust hole; 13. pressing a limiting hole; 2. a structural template; 3. forming a frame; 31. a side wall; 32. an upper edge; 33. packaging the limiting hole; 4. a gland; 41. polydimethylsiloxane prepolymer addition holes; 42. fixing a column; 43. an inner concave portion; 44. an assembling portion; 5. cutting into a section.

Detailed Description

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In order to overcome the stable accurate cutting that is difficult to realize PDMS in the preparation of present micro-fluidic chip, the embodiment of the utility model provides an utilize the shaping frame to enclose into polydimethylsiloxane prepolymer and hold the chamber with the structure template, prepare micro-fluidic chip like this and need not cut PDMS, simultaneously, the PDMS that can also control the production keeps unanimous between the batch thickness.

Referring to fig. 1 to 3, an embodiment of the present invention discloses a polydimethylsiloxane micro-fluidic chip preparation mold, which includes: the structure comprises a bottom plate 1, a structure template 2, a forming frame 3 and a gland 4.

The base plate 1 is a metal base plate, that is, the base plate 1 is made of a metal material, including but not limited to aluminum alloy, stainless steel, etc.

The bottom plate 1 is provided with a groove 11. Further, the groove 11 includes: hold the chamber down and hold the chamber on, hold the chamber down and hold the chamber on and be used for successively placing structure template 2 and forming frame 3 respectively, promptly, hold under the embedding of structure template 2 and hold the chamber, forming frame 3 puts into and holds in the chamber.

The structural template 2 is made of a silicon wafer or other materials for forming the PDMS microfluidic chip structure. Further, the upper surface of the silicon chip is provided with a microstructure. The microstructure can be formed on the silicon chip by the MEMS process and transferred to the PDMS material by pouring to obtain the PDMS microfluidic chip. Namely, the PDMS prepolymer is poured on a silicon chip and waits for the completion of curing, and the micro structure on the cured silicon chip is transferred on PDMS.

The structural formwork 2 is inserted into the lower receiving cavity in the recess 11 in the base plate 1 before the first use of the mould, and the structural formwork 2 is cut precisely so that no excess gap exists between the structural formwork 2 and the lower receiving cavity. Thus, after curing, no unnecessary portions, such as burrs, etc., are generated at the position where the structural template 2 is bonded to the PDMS.

The lower surface of the structural formwork 2 is closely adhered to the base plate 1 using an adhesive. Preferably, the bottom of the recess 11 is provided with a plurality of vents 12, the vents 12 being arranged in a square array at the bottom of the recess 11 as shown in fig. 1. When the structural template 2 is adhered to the bottom plate 1, the gas in the adhesive can be exhausted through the exhaust holes 12, so that the bottom plate 1 and the structural template 2 are tightly adhered. At the same time, the excess adhesive is discharged into the exhaust holes 12, ensuring that the structural formwork 2 is laid flat at the bottom of the groove 11.

The adhesive can be selected from polydimethylsiloxane adhesive, and PDMS has good adhesion with silicon wafer. The polydimethylsiloxane adhesive is easy to generate gas during the bonding process with the silicon wafer, and bubbles are formed. Therefore, the vent hole 12 is arranged at the bottom of the groove 11, and the generated gas can be effectively discharged through the vent hole 12, so that the adhesion effect is prevented from being influenced. In addition, the bubbles can cause the structural template 2 not to be flatly laid at the bottom of the groove 11, which seriously affects the quality of the finished product of the polydimethylsiloxane microfluidic chip.

The forming frame 3 is made of plastic materials including but not limited to PC, PMMA, ABS, PP and the like, and the forming frame 3 is a disposable consumable product and is used for wrapping polydimethylsiloxane prepolymer.

When the forming frame 3 is used, the forming frame is placed into the upper containing cavity of the groove 11 and is tightly attached to the contact surface in the upper containing cavity. Specifically, the forming frame 3 includes an integrally formed sidewall 31 and an outwardly extending upper edge 32, and the sidewall 31 closely fits to the contact surface in the upper receiving cavity.

The embodiment of the utility model provides an in, hold the chamber down and be greater than and hold the chamber, hold the chamber down and form spacing step with the position that the last chamber that holds meets. The forming frame 3 is placed on the limiting step, and the lower surface of the forming frame 3 is attached to the structure template 2.

The gland 4 is a metal gland, that is, the gland 4 is made of metal material, including but not limited to aluminum alloy, stainless steel, etc. The gland 4 is press-fitted on the base plate 1, and the middle of the gland 4 is hollowed out to form a polydimethylsiloxane prepolymer charging hole 41 for pouring polydimethylsiloxane prepolymer.

A plurality of fixing posts 42 are provided under the gland 4 around the polydimethylsiloxane prepolymer charging hole 41. Correspondingly, a plurality of press-fitting limiting holes 13 are formed around the groove 11 on the bottom plate 1. The embodiment of the utility model provides an in, the quantity of fixed column 42 and the spacing hole 13 of pressure equipment is the same, as shown in fig. 1, bottom plate 1 and gland 4 are the square, consequently, the quantity of fixed column 42 and the spacing hole 13 of pressure equipment is preferred four, sets up a fixed column 42 in every angular position of gland 4, correspondingly, sets up the spacing hole 13 of pressure equipment in every angular position of bottom plate 1, and every fixed column 42 realizes spacing fixedly in inserting the spacing hole 13 of pressure equipment on bottom plate 1 when the assembly.

Referring to fig. 3, a fitting portion 44 is formed to extend downward at a position around the polydimethylsiloxane prepolymer charging hole 41 below the cap 4, the inner contour of the fitting portion 44 matches the outer contour of the upper edge 32 of the molding frame 3, and the cap 4 is tightly fitted to the upper portion of the molding frame 3 through the fitting portion 44. Thus, the structural formwork 2 and the forming frame 3 enclose a polydimethylsiloxane prepolymer accommodating cavity.

Referring to fig. 3, the forming frame 3 is press-fitted between the pressing cover 4 and the bottom plate 1 through the fixing posts 42, a gap may exist between the pressing cover 4 and the bottom plate 1, the forming frame 3 may have different heights as required, and the size of the gap between the pressing cover 4 and the bottom plate 1 may be adjusted through the fixing posts 42 to meet the requirements of press-fitting the forming frames 3 of different heights.

Referring to fig. 1, a plurality of package limiting holes 33 are formed in a side wall 3 of the mold frame 3, and fig. 1 shows that the number of the package limiting holes 33 is 3. The package limiting hole 33 is used in a packaging step after obtaining the polydimethylsiloxane microfluidic chip with the molding frame as an outer frame.

Referring to fig. 1 and 2, the opposite side of the gland 4 is provided with an inner recess 43, and the gland 4 can be press-fitted or removed by holding the inner recess 43 by hand. Since the pressing cover 4 is made of a metal material and has a certain weight, the arrangement of the concave portion 43 facilitates the operation of the pressing cover 4.

Preferably, with reference to fig. 1, the bottom plate 1, the forming frame 3 and the gland 4 are provided with a cut 5 at the same facing corner position. In this way, when assembling the base plate 1, the forming frame 3 and the pressing cover 4, the corners having the cut surfaces 5 are aligned, and it is possible to ensure that the mounting direction of the base plate 1, the forming frame 3 and the pressing cover 4 is correct.

In order to solve the problem, the embodiment of the utility model also discloses a polydimethylsiloxane micro-fluidic chip preparation method corresponding to the polydimethylsiloxane micro-fluidic chip preparation mould disclosed above.

The embodiment of the utility model discloses a polydimethylsiloxane micro-fluidic chip preparation method includes: before the first use, the structural formwork 2 is inserted into the groove 11 of the base plate 1; placing the forming frame 3 into the groove 11, pressing the gland 4 on the bottom plate 1, pressing the forming frame 3 tightly, and enclosing the structure template 2 and the forming frame 3 to form a polydimethylsiloxane prepolymer accommodating cavity; a predetermined amount of polydimethylsiloxane prepolymer is poured through a polydimethylsiloxane prepolymer charging hole 41 formed by hollowing out the middle of the gland 4; putting the whole prepolymer-containing mould into a closed container, and vacuumizing until no bubbles are generated; transferring the whole mould into a heating device (such as an oven and the like) under a vacuum condition for heating until the liquid is completely solidified; and integrally taking out the mold, taking down the gland 4, slowly and uniformly taking out the forming frame 3, and ensuring that the solidified polydimethylsiloxane is taken out along with the forming frame 3 to obtain the polydimethylsiloxane microfluidic chip taking the forming frame 3 as an outer frame.

Further, after the pressing cover 4 is pressed on the base plate 1, the side wall 31 of the forming frame 3 is closely attached to the inner surface of the groove 11, the upper edge 32 of the forming frame 3 is fitted with the fitting portion 44 of the pressing cover 4, and the pressing cover 4 presses the forming frame 3 through the upper edge 32.

The embodiment of the utility model provides an in preparation polydimethylsiloxane micro-fluidic chip, the PDMS that need not to take out after the PDMS solidification cuts, has effectively solved the problem that is difficult to realize the stable accurate cutting of PDMS in the present micro-fluidic chip preparation. In addition, the polydimethylsiloxane prepolymer containing cavity is defined by the surrounding of the structural template and the forming frame 3, so that the prepared polydimethylsiloxane microfluidic chip is accurate in three-dimensional size and high in batch-to-batch uniformity.

Preferably, the structural formwork 2 is tightly bonded to the bottom of the groove 11 by means of an adhesive, which comprises: using adhesive to lay a layer of adhesive layer at the bottom of the groove 11 of the bottom plate 1; the structural template 2 is placed on the adhesive layer and is forced downwards, the gas in the adhesive layer is exhausted from the plurality of exhaust holes 12, the redundant adhesive enters the exhaust holes 12, and the structural template 2 is flatly laid at the bottom of the groove 11.

Before the first use, the structural template 2 and the bottom plate 1 are directly bonded into a whole by an adhesive, so that the polydimethylsiloxane micro-fluidic chip can be conveniently and repeatedly prepared for many times. In the bonding process, the air is exhausted in time through the exhaust holes 12, and the bottom plate 1 and the structural template 2 are tightly bonded. At the same time, the excess adhesive is discharged into the exhaust holes 12, ensuring that the structural formwork 2 is laid flat at the bottom of the groove 11.

The embodiment of the utility model provides an in, the preferred polydimethylsiloxane adhesive of adhesive, have good adhesion between PDMS and the silicon chip.

Further, when a predetermined amount of the polydimethylsiloxane prepolymer is poured, the liquid level of the polydimethylsiloxane prepolymer is not higher than the upper surface of the molding frame 3.

The embodiment of the utility model provides an in preparation polydimethylsiloxane micro-fluidic chip, require lowly to PDMS prepolymer application of sample volume precision before the PDMS solidification. Due to the limitation of the molding frame, the liquid level of the added PDMS prepolymer liquid is not higher than the highest point of the molding frame, and the height of the prepared microfluidic chip is the height of the molding frame, so that the thickness of the microfluidic chip can be conveniently controlled in the preparation process.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims

1. The polydimethylsiloxane micro-fluidic chip preparation mold is characterized by comprising the following components in parts by weight: bottom plate, structural template, shaping frame and gland, set up the recess on the bottom plate, the recess bottom is provided with a plurality of exhaust holes, the recess includes: the structure template is embedded into the lower accommodating cavity, the forming frame is placed into the upper accommodating cavity, the gland is pressed on the bottom plate, and the middle of the gland is hollowed to form a polydimethylsiloxane prepolymer adding hole.

2. The mold for preparing a polydimethylsiloxane micro-fluidic chip according to claim 1, wherein the lower accommodating cavity is larger than the upper accommodating cavity, and a position where the lower accommodating cavity is connected with the upper accommodating cavity forms a limiting step.

3. The mold for preparing a polydimethylsiloxane micro-fluidic chip according to claim 2, wherein the bottom plate is a metal bottom plate, and a plurality of press-fitting limiting holes are arranged around the groove.

4. The mold for preparing a polydimethylsiloxane micro-fluidic chip according to claim 1, wherein the structural template is a silicon wafer formed by accurate cutting, and the upper surface of the silicon wafer is provided with a microstructure.

5. The mold for preparing a polydimethylsiloxane micro-fluidic chip according to claim 4, wherein the lower surface of the structural template is tightly adhered to the bottom of the groove by using an adhesive.

6. The mold for preparing a microfluidic polydimethylsiloxane chip of claim 1, wherein the molding frame comprises a side wall and an upper edge, the side wall and the upper edge are integrally formed by using a plastic material.

7. The mold for preparing a polydimethylsiloxane micro-fluidic chip according to claim 6, wherein a plurality of packaging limiting holes are formed in a side wall of one side of the molding frame.

8. The mold for preparing the polydimethylsiloxane micro-fluidic chip according to claim 1, wherein the gland is a metal gland, a plurality of fixing columns are arranged below the gland around the polydimethylsiloxane prepolymer adding hole, and the fixing columns are inserted into the bottom plate to realize limiting and fixing during assembly.

9. The polydimethylsiloxane microfluidic chip preparation mold of claim 8, wherein opposing sides of the gland are provided with recessed portions.

10. The mold for preparing polydimethylsiloxane microfluidic chips of any one of claims 1 to 9, wherein the bottom plate, the molding frame and the pressing cover are provided with a tangent plane at the same facing corner position.