阅读说明：本技术 一种可重复使用的同轴毛细管微流控芯片及其制备方法 (Reusable coaxial capillary microfluidic chip and preparation method thereof ) 是由 陶胜洋 冯时 杨文博 于 2020-12-17 设计创作，主要内容包括：本发明属于微流控芯片技术领域,具体是一种可重复使用的同轴毛细管微流控芯片及其制备方法。芯片包括基底,对阵平台,对针器和接收器,基底上开设有孔作为视窗；视窗两侧分别固定有对针平台,对针平台一侧开设带有内螺纹的孔一；对针平台内部同轴线上从孔一依次设置圆形槽一、方形槽；方形毛细管的两端分别置于两个对针平台的方形槽内,接收器和对针器分别置于两个对针平台的孔一内；一根圆形毛细管一端固定于接收器,另一端置于方形毛细管内；另一根圆形毛细管一端固定于对针器,另一端置于方形毛细管内。本发明实现了同轴玻璃微流控芯片的重复使用,保证了圆形毛细管在方形管内的同轴准确排列,并可随时调节两个根圆形毛细管之间的距离。(The invention belongs to the technical field of microfluidic chips, and particularly relates to a reusable coaxial capillary microfluidic chip and a preparation method thereof. The chip comprises a substrate, an array platform, a needle aligner and a receiver, wherein a hole is formed in the substrate and is used as a window; a first hole with internal threads is formed in one side of the needle aligning platform; a first circular groove and a first square groove are sequentially arranged on the coaxial line in the needle alignment platform from the first hole; two ends of the square capillary tube are respectively arranged in the square grooves of the two needle aligning platforms, and the receiver and the needle aligning device are respectively arranged in the holes I of the two needle aligning platforms; one end of a round capillary tube is fixed on the receiver, and the other end of the round capillary tube is arranged in the square capillary tube; one end of the other round capillary is fixed on the needle aligning device, and the other end of the other round capillary is arranged in the square capillary. The invention realizes the repeated use of the coaxial glass microfluidic chip, ensures the coaxial and accurate arrangement of the circular capillaries in the square tube, and can adjust the distance between the two circular capillaries at any time.)

1. The utility model provides a coaxial capillary micro-fluidic chip, includes circular capillary (1), square capillary (2), its characterized in that still includes:

the device comprises a substrate (3), wherein a hole is formed in the substrate to serve as a window (4);

the device comprises two needle aligning platforms (5), wherein one side of each needle aligning platform is provided with a first hole (5-1) with an internal thread; a first circular groove (5-2) and a second square groove (5-3) are sequentially arranged on the coaxial line in the needle alignment platform from the first hole;

the needle aligning device (6) is a cylinder with external threads and is matched with the first hole (5-1), and a second circular groove (6-2) is formed in the needle aligning device and used for fixing a circular capillary tube;

the receiver (7) is a cylinder with external threads and matched with the first hole (5-1), and a third circular groove (7-2) is formed in the receiver to fix the circular capillary tube;

the two needle aligning platforms (5) are respectively fixed on two sides of a window (4) on the substrate (3); two ends of the square capillary tube are respectively arranged in the square grooves (5-3) of the two needle aligning platforms, and the receiver and the needle aligning device are respectively arranged in the holes (5-1) of the two needle aligning platforms; one end of a round capillary tube is fixed on the receiver (7), and the other end of the round capillary tube is arranged in the square capillary tube (2); one end of the other round capillary tube is fixed on the needle aligning device (6), and the other end is arranged in the square capillary tube (2).

2. The coaxial capillary microfluidic chip according to claim 1, wherein two ends of the needle aligner are respectively provided with a second hole (6-1) and a third hole (6-3) with internal threads, and the second hole (6-1) is communicated with the third hole (6-3) through a circular groove (6-2); one end of the receiver close to the first hole (5-1) is provided with a fourth hole (7-1) with internal threads, and the fourth hole (7-1) is communicated with the third circular groove (7-2); the inner diameters of the second hole (6-1), the third hole (6-3) and the fourth hole (7-1) are matched with the inverted cone joint; preferably, one end of the receiver circular groove III (7-2) is provided with a knob, and one end of the needle aligning device hole III (6-3) is provided with a knob.

3. The coaxial capillary microfluidic chip according to claim 1, wherein the circular groove one (5-2) is composed of a first circular groove (5-2-1) and a second circular groove (5-2-2), and the inner diameter of the first circular groove (5-2-1) adjacent to the square groove (5-3) is smaller than the inner diameter of the second circular groove (5-2-2) adjacent to the hole one (5-1); preferably, a sleeve is sleeved outside the circular capillary tube, the outer diameter of the sleeve is matched with the inner diameter of the second circular groove, and the inner diameter of the first circular groove is matched with the outer diameter of the circular capillary tube; the inner diameter of the square groove is matched with the outer diameter of the square capillary.

4. The coaxial capillary microfluidic chip according to claim 1, wherein the top of the probe platform is provided with a liquid inlet hole (5-4) communicated with the square groove (5-3).

5. The microfluidic chip according to claim 1, wherein the window is disposed in the center of the substrate, and the window is a rectangular channel for observing the alignment of two round capillaries in a square capillary.

6. The coaxial capillary microfluidic chip according to claim 1, wherein the length of the first hole and the length of the receiver are such that the receiver is screwed into the first hole for a distance that the ground end of the round capillary moves within the window of the square capillary; the length of the first hole and the length of the needle aligning device meet the requirement that the receiver is screwed into the first hole for a distance, so that the polished end of the round capillary tube moves within the range of the window in the square capillary tube.

7. A coaxial capillary microfluidic chip according to claim 1, wherein the two needle platforms are provided with a groove (5-5) on the opposite side, and a holder (5-6) is placed in the groove for holding a square capillary; the fixer is a cylinder and is matched with the groove in size.

8. A preparation method of a coaxial capillary microfluidic chip is characterized by comprising the following steps:

(1) drawing and printing: drawing a substrate, a needle aligning platform, a receiver and a needle aligning device by drawing software; printing by using a 3D printing technology;

(2) polishing the round capillary: polishing one end of a round capillary tube into a required conical head;

(3) and (3) mounting and fixing: fixing two ends of a square capillary tube in the square grooves of the two needle aligning platforms respectively; fixing the unpolished end of one round capillary tube on a needle aligner, and fixing the unpolished end of the other round capillary tube on a receiver;

(4) adjusting the position: the needle aligning device and the receiver are respectively screwed into the first two needle aligning platform holes, one polished end of the circular capillary enters the square groove through the first circular groove and is arranged in the square capillary, and the relative distance of the two circular capillaries is adjusted by screwing the needle aligning device and the receiver to be coaxially aligned in the square capillary.

9. The method for preparing a coaxial capillary microfluidic chip according to claim 8, wherein in the step (3), two ends of the square capillary are respectively fixed in the square groove of the pin platform, and then the square capillary is fixed in the groove by a fixer and further sealed by epoxy glue.

10. The method for preparing a coaxial capillary microfluidic chip according to claim 8, wherein in the step (3), the non-polished end of a round capillary is placed in the sleeve and then placed in the inverted cone connector, and the inverted cone connector is screwed into the hole II (6-1) to fix the non-polished end of the round capillary in the circular groove II (6-2) of the needle aligner; and an inverted cone joint used by the other round capillary is screwed into the hole IV (7-1) and fixed in the round groove III (7-2) of the receiver by the same method.

Technical Field

The invention belongs to the technical field of microfluidic chips, and particularly relates to a reusable coaxial capillary microfluidic chip and a preparation method thereof.

Background

The coaxial glass capillary microfluidic chip is a widely used core-shell microcapsule production device. The microcapsule with core-shell structure has wide application range, and has the potential of deep excavation from controlled release of medicine and nutrient substances to rapid detection of trace liquid, molecular capture and the like. The traditional coaxial glass capillary microfluidic chip device consists of two round capillaries with conical heads, which are coaxially and oppositely arranged in a square capillary and are spaced at a certain distance from each other. The traditional device is easy to have the problem that the square capillary and the circular capillary can not ensure coaxial alignment in the manufacturing process, which can directly cause that the chip can not normally generate the capsule with a core-shell structure. On the other hand, the existing coaxial glass capillary microfluidic chips are all disposable, and when liquid flows, if blockage occurs, the liquid cannot flow normally, so that the chips are scrapped; in addition, the circular capillaries are mostly fixed by epoxy glue and cannot move, and in the experimental process, if the relative distance between the two circular capillaries is not appropriate, and the distance cannot be moved and adjusted after the two circular capillaries are fixed, qualified microcapsules with a core-shell structure cannot be generated; meanwhile, the traditional chip is mostly made of fragile materials such as glass, and after improvement, the chip can be made of materials such as metal and polymer, so that the chip is more durable when observation is not influenced.

Therefore, the design and preparation process of the existing coaxial glass capillary microfluidic chip are improved, the chip can be reused on the premise of ensuring the coaxial and accurate arrangement in the square capillary, and meanwhile, the relative distance of the round capillary can be flexibly changed, so that the size of the generated microcapsule can be adjusted, and the chip has important application value for the production of core-shell microcapsules.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides the reusable coaxial capillary microfluidic chip and the preparation method thereof, and the reusable coaxial capillary microfluidic chip can be rapidly manufactured by using a 3D printing technology.

In order to realize the purpose, the invention adopts the following technical scheme:

the invention provides a coaxial capillary microfluidic chip, which comprises a round capillary and a square capillary, and also comprises:

the device comprises a substrate, a first electrode and a second electrode, wherein holes are formed in the substrate to be used as windows;

the device comprises two needle aligning platforms, wherein one side of each needle aligning platform is provided with a first hole with an internal thread; a first circular groove and a first square groove are sequentially arranged on the coaxial line in the needle alignment platform from the first hole;

the needle aligning device is a cylinder with external threads, is matched with the first hole, and is internally provided with a circular groove II for fixing a circular capillary tube;

the receiver is a cylinder with external threads and is matched with the first hole, and a circular groove is formed in the receiver for three purposes to fix the circular capillary;

the two needle aligning platforms are respectively fixed on two sides of the window on the substrate; two ends of the square capillary tube are respectively arranged in the square grooves of the two needle aligning platforms, and the receiver and the needle aligning device are respectively arranged in the first holes of the two needle aligning platforms; one end of a round capillary tube is fixed on the receiver, and the other end of the round capillary tube is arranged in the square capillary tube; one end of the other round capillary is fixed on the needle aligning device, and the other end of the other round capillary is arranged in the square capillary.

In the technical scheme, furthermore, a hole II and a hole III with internal threads are respectively formed at two ends of the needle aligner, and the hole II is communicated with the hole III through a circular groove II; one end of the receiver close to the first hole is provided with a fourth hole with internal threads, and the fourth hole is communicated with the third circular groove; the inner diameters of the second hole, the third hole and the fourth hole are matched with the inverted cone joints; preferably, a knob is arranged at one end of the receiver circular groove III, and a knob is arranged at one end of the needle aligning device hole III.

In the above technical solution, further, the first circular groove consists of a first circular groove and a second circular groove, and an inner diameter of the first circular groove close to the square groove is smaller than an inner diameter of the second circular groove close to the first hole; preferably, a sleeve is sleeved outside the circular capillary tube, the outer diameter of the sleeve is matched with the inner diameter of the second circular groove, and the inner diameter of the first circular groove is matched with the outer diameter of the circular capillary tube; the inner diameter of the square groove is matched with the outer diameter of the square capillary.

Among the above-mentioned technical scheme, further, liquid inlet hole and square groove intercommunication have been seted up to the needle platform top.

In the above technical solution, further, the window is disposed at the center of the substrate, and the window is a rectangular hole for observing alignment conditions in two circular capillaries in a square capillary.

In the technical scheme, furthermore, the length of the first hole and the length of the receiver meet the requirement that the receiver is screwed into the first hole for a distance so that the polished end of the round capillary tube moves within the range of the window in the square capillary tube; the length of the first hole and the length of the needle aligning device meet the requirement that the receiver is screwed into the first hole for a distance, so that the polished end of the round capillary tube moves within the range of the window in the square capillary tube.

In the above technical solution, further, a groove is provided at one side of the two needle alignment platforms opposite to each other, and a fixer is placed in the groove for fixing the square capillary; the fixer is a cylinder and is matched with the groove in size.

The invention also provides a preparation method of the coaxial capillary microfluidic chip, which comprises the following steps:

(1) drawing and printing: drawing a substrate, a needle aligning platform, a receiver and a needle aligning device by drawing software; printing by using a 3D printing technology;

(2) polishing the round capillary: polishing one end of a round capillary tube into a required conical head;

(3) and (3) mounting and fixing: fixing two ends of a square capillary tube in the square grooves of the two needle aligning platforms respectively; fixing the unpolished end of one round capillary tube on a needle aligner, and fixing the unpolished end of the other round capillary tube on a receiver;

(4) adjusting the position: the needle aligning device and the receiver are respectively screwed into the first two needle aligning platform holes, one polished end of the circular capillary enters the square groove through the first circular groove and is arranged in the square capillary, and the relative distance of the two circular capillaries is adjusted by screwing the needle aligning device and the receiver to be coaxially aligned in the square capillary.

In the above technical scheme, further, in the step (3), two ends of the square capillary tube are respectively fixed in the square groove of the needle alignment platform, and then the fixer is placed in the groove to fix the square capillary tube, and the square capillary tube is further sealed by epoxy glue.

In the above technical scheme, further, in the step (3), the non-polished end of the circular capillary tube is firstly placed in the sleeve and then placed in the inverted cone joint, and the inverted cone joint is screwed into the hole II to fix the non-polished end of the circular capillary tube in the circular groove II of the needle aligner; and an inverted cone joint used by the other round capillary is screwed into the hole IV and fixed in the round groove III of the receiver by the same method.

The invention has the beneficial effects that: the invention realizes the repeated use of the coaxial glass microfluidic chip by utilizing the 3D printing technology and a special chip structure, ensures the coaxial and accurate arrangement of the circular capillaries in the square tube, and can adjust the distance between the two circular capillaries at any time according to the condition of generating capsules in an experiment so as to prepare the required core-shell structure microcapsule; the round capillary tube is not fixed by glue, can be detachably cleaned, can be subjected to other modifications, and changes a hydrophilic surface into a hydrophobic surface without manufacturing a chip again; the fittings of the microfluidic chip can be manufactured in large quantity, have high repeatability, do not need further processing, and are directly assembled during use, so that the time cost is saved.

Drawings

FIG. 1 is a schematic diagram of a chip of the present invention;

FIG. 2 is a cross-sectional view of a chip structure according to the present invention;

FIG. 3 is a cross-sectional view of a chip with a receiver structure according to the present invention;

FIG. 4 is a schematic diagram of a chip structure according to the present invention;

FIG. 5 is a schematic view of the structure of the needle aligning device of the present invention;

FIG. 6 is a cross-sectional view of the needle aligning device of the present invention;

FIG. 7 is a schematic diagram of a receiver according to the present invention;

FIG. 8 is a cross-sectional view of a receiver structure according to the present invention;

FIG. 9 is a schematic view of the fastener of the present invention;

in the figure, 1 is a circular capillary tube, 2 is a square capillary tube, 3 is a substrate, 4 is a window, 5 is a needle alignment platform, 5-1 is a hole I, 5-2 is a circular groove I, 5-3 is a square groove, 5-4 is a liquid inlet hole, 5-5 is a groove, 6 is a needle alignment device, 6-1 is a hole II, 6-2 is a circular groove II, 6-3 is a hole III, 7 is a receiver, 7-1 is a hole IV, 7-2 is a circular groove III, 8 is a fixer, 9 is an FEP sleeve, 10 is an inverted cone connector, and 11 is a ring blade.

Detailed Description

The invention is further illustrated but is not in any way limited by the following specific examples.

Example 1

The utility model provides a coaxial capillary micro-fluidic chip, includes two circular capillaries 1, square capillary 2, still includes:

the device comprises a substrate 3, wherein a hole is formed in the substrate to serve as a window 4, the window is arranged in the center of the substrate and is a rectangular pore channel used for observing the alignment condition of two circular capillaries in a square capillary.

The needle alignment platform 5 is provided with two needle alignment platforms, and one side of each needle alignment platform is provided with a first hole 5-1 with an internal thread; a groove 5-5 is arranged on one side opposite to the first hole, and a fixer 5-6 is arranged in the groove for fixing the square capillary tube; the fixer is a cylinder and is matched with the groove in size; a first circular groove 5-2 and a second circular groove 5-2-2 are sequentially arranged between the first hole and the groove on the coaxial line in the needle platform, the first circular groove 5-2 is composed of a first circular groove 5-2-1 and a second circular groove 5-2-2, and the inner diameter of the first circular groove 5-2-1 close to the second circular groove 5-3 is smaller than that of the second circular groove 5-2-2 close to the first hole 5-1; the circular capillary tube is sleeved with a sleeve, the outer diameter of the sleeve is matched with the inner diameter of the second circular groove, and the inner diameter of the first circular groove is matched with the outer diameter of the circular capillary tube; the inner diameter of the square groove is matched with the outer diameter of the square capillary; the top of the array platform is provided with a liquid inlet hole 5-4 communicated with the square groove 5-3;

the needle aligning device is a cylinder with external threads and is matched with the first hole 5-1, a second circular groove 6-2 is formed in the needle aligning device, the two ends of the needle aligning device are respectively provided with a second hole 6-1 and a third hole 6-3 with internal threads, and the second circular groove 6-2 is used for communicating the second hole 6-1 with the third hole 6-3 and fixing a circular capillary tube; one end of the needle aligning device hole III 6-3 is provided with a knob;

the receiver is a cylinder with external threads and is matched with the first hole 5-1, a third circular groove 7-2 is formed in the receiver, a fourth hole 7-1 with internal threads is formed in one end, close to the first hole 5-1, of the receiver, and the fourth hole 7-1 is communicated with the third circular groove 7-2 and used for fixing a circular capillary tube; one end of the receiver circular groove III 7-2 is provided with a knob, so that the receiver circular groove III can be conveniently screwed by hand;

the two needle aligning platforms are fixed on two sides of the window on the substrate; two ends of the square capillary tube are respectively arranged in the square grooves 5-3 of the two needle aligning platforms, the receiver and the needle aligning device are respectively arranged in the holes 5-1 of the two needle aligning platforms, one round capillary tube penetrates through the receiver and is arranged in the square capillary tube, and the other capillary tube penetrates through the needle aligning device and is arranged in the square capillary tube.

Example 2

The coaxial capillary microfluidic chip is prepared by selecting plastic, metal, high polymer materials and the like as the substrate, wherein the plastic substrate is selected in the embodiment, and the preparation method comprises the following steps:

(1) drawing and printing: drawing a substrate, a needle aligning platform, a receiver and a needle aligning device by drawing software; printing by using a 3D printing technology;

(2) polishing the round capillary: circular borosilicate capillaries were tapered to the desired diameter with a glass needle tube maker, which was ground into conical needles using a glass microelectrode (needle tube) grinder. The obtained tapered glass capillary tube was washed and dried to remove residual glass particles. Soaking the capillary tube in 30% H₂O₂And 98% H₂SO₄In a ratio of 3: 7, cleaning the mixture by using air and ethanol, and treating the mixture for 1 minute by using octadecyltrimethoxysilane to make the mixture hydrophobic for later use;

(3) and (3) mounting and fixing: fixing two ends of a square borosilicate capillary tube in square grooves of two needle alignment platforms respectively, then placing a fixer in the groove to fix the square capillary tube, and further fixing and sealing by epoxy glue;

placing the unpolished end of the circular capillary tube into the FEP sleeve firstly, extending the unpolished tail end of the circular capillary tube out of the sleeve by about 4mm, and then placing the capillary tube into an inverted cone joint, wherein the inverted cone joint is screwed into the hole II 6-1 to be matched with the annular blade to fix the unpolished end of the circular capillary tube to the needle aligner, and the FEP sleeve section is placed in the circular groove I to form a sealing structure; fixing another round capillary tube to the receiver by the same method;

(4) adjusting the position: after the tightness is checked, the needle aligning device and the receiver are screwed into the first two aligning platform holes respectively, the non-polished end of the circular capillary tube enters the second square groove through the first circular groove, the two circular capillary tubes are placed in the square capillary tube, the positions of the two circular capillary tubes are observed through a window, the relative distance between the two circular capillary tubes is adjusted by screwing the needle aligning device and the receiver, and the two circular capillary tubes are coaxially aligned in the square capillary tube.

Example 3

According to the preparation method of the invention, the chip substrate can be prepared in batch, the needle aligning device, the receiver and the fixer are reserved, when an experiment is needed, the round glass capillary tube is ground, the round capillary tube is placed in the square capillary tube according to the method in the embodiment 2 to be coaxially aligned, and the relative distance between the two round capillary tubes is adjusted for the needle aligning device and the receiver.

When the device is used, the inverted cone connector is screwed into the two liquid inlets and the hole III 6-3 of the needle counter respectively, and after liquid enters the device, a test is carried out, and the microcapsule is obtained from one side of the circular groove III 7-2 of the receiver.

In the experiment process, when the relative position between the two capillary tubes needs to be adjusted, the needle aligner and the receiver are rotated.

When the capillary tube is blocked, the capillary tube is detached by rotating the needle aligning device and the receiver, and the capillary tube is dredged and cleaned and then is used continuously.

It will be apparent to those skilled in the art from this disclosure that many changes and modifications can be made, or equivalents modified, in the embodiments of the invention without departing from the scope of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention shall still fall within the protection scope of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.