CN114768903A - A microfluidic chip quantitative sample adding device - Google Patents

Abstract

The invention discloses a quantitative sample adding device for a microfluidic chip, comprising a sample adding pool; the top of the sample adding pool is open, the bottom end is closed, and the lower part is sequentially communicated with the sample introduction microchannel, the reaction pool and the air hole on the microfluidic chip ; An overflow pool is formed on the outside of the sample adding pool, and an overflow space is formed between the overflow pool and the sample adding pool; the upper part of the sample adding pool has an overflow channel connecting the sample adding pool and the overflow pool. The invention provides a microfluidic chip quantitative sample adding device. By setting the overflow pool around the sample adding pool, the excess liquid sample can be automatically received after the sample injection is completed in the reaction pool and the microchannel in the chip, without the need for external auxiliary equipment to quantitatively send the sample. sample, suitable for any sample tube and loading method. And the chip based on the device is simple in structure and simple in processing technology, so it is easy to realize matching with different systems, and can also meet the requirements of mass production and low cost. The invention can be used for quantitative detection in the fields of biology, chemistry, medicine and the like, and is especially suitable for the field of POCT.

Description

A microfluidic chip quantitative sample adding device

technical field

The invention relates to the technical field of microfluidic chips, in particular to a quantitative sample adding device for microfluidic chips.

Background technique

For sudden diseases such as myocardial infarction, the traditional process of sampling, sending samples, and collecting inspection cannot meet the requirements of rapid diagnosis, and with the improvement of people's living standards, the demand for daily health monitoring is gradually increasing. POCT (Point-of-Care Testing, point-of-care testing, also known as point-of-care testing) technology can perform rapid testing and diagnosis around patients. Its technical advantages are mainly reflected in: simple operation, no need for professionals; reduced sample transmission, saving Assay time; portable instruments and reagents. It is especially suitable for the layout of primary medical institutions, airports, communities and other places, and home self-inspection.

Microfluidic chip refers to the integration of basic operating units such as sample preparation, reaction, separation, and detection in biological, chemical, and medical analysis processes on a chip of several centimeters in size, and the entire analysis process is automatically completed. Compared with traditional laboratory analysis, it has the advantages of small volume, low sample consumption and fast analysis speed. Therefore, microfluidic chips have broad application prospects in the functional integration of POCT products.

The premise of quantitative analysis of trace samples on a microfluidic chip is the quantification of the reaction volume. Usually, a reaction cell structure with a certain volume is microfabricated on the microfluidic chip. When adding a sample, the sample volume is calculated based on the standard of filling the reaction cell. In order to complete the quantitative sample addition, the existing technical means include: 1) Pipette sample addition, use the pipette to absorb the specified volume and then press the sample injection port to the chip, according to the different sample volume needs to be equipped with different ranges of pipettes; It is difficult for non-professionals to operate liquid dispensers and pipette tips; 2) Capillary injection, sampling can be easily achieved through capillary action, but it cannot be accurately quantified due to factors such as differences in liquid samples; 3) Syringe injection For example, the manual mode and the automatic injection mode of the syringe pump, respectively, need to independently design the joint matching the chip injection port to complete the quantitative injection; 4) Precision pump valve equipment, including air pump, peristaltic pump, etc., and surrounding these pump valves The integrated automatic pipetting station can complete the quantitative addition of microfluidic chips with high throughput and high precision, but it is bulky and expensive. Based on the above analysis, the existing quantitative sample addition methods have very high requirements on personnel, equipment and costs.

Therefore, how to provide an on-site detection and sample adding device with low cost, simple operation and strong applicability is an urgent problem to be solved by those skilled in the art.

SUMMARY OF THE INVENTION

In view of this, the present invention provides a microfluidic chip quantitative sample adding device, aiming at solving the above technical problems.

In order to achieve the above object, the present invention adopts the following technical solutions:

A microfluidic chip quantitative sample adding device, comprising a sample adding pool; the top of the sample adding pool is open, the bottom end is closed, and the lower part is sequentially communicated with sample introduction microchannels, reaction pools and air holes on the microfluidic chip; An overflow pool is formed on the outside of the sample adding pool, and an overflow space is formed between the overflow pool and the sample adding pool; the upper part of the sample adding pool has an overflow channel that communicates with the sample adding pool and the overflow pool.

Through the above technical solutions, the present invention provides a microfluidic chip quantitative sample adding device, through the setting of overflow pools around the sample adding pool, it can automatically receive excess liquid samples after the in-chip reaction pool and microchannel complete the sample injection, without the need for External auxiliary equipment for quantitative sample delivery, suitable for any sample tube and sample loading method. In addition, the chip based on the device has a simple structure and a simple processing technology, so it is easy to achieve matching with different systems, and can also meet the requirements of batch manufacturing and low cost. The invention can be used for quantitative detection in the fields of biology, chemistry, medicine and the like, and is especially suitable for the field of POCT.

Preferably, in the above-mentioned microfluidic chip quantitative sample adding device, the overflow can be realized by the cooperation of the height difference between the top edge of the sample adding tank and the overflow tank, or the overflow can be realized by opening holes; a water-absorbing material can be arranged in the overflow tank. , or cover the top edge of the overflow pool with a hydrophobic breathable membrane.

As can be seen from the above technical solutions, compared with the prior art, the present invention provides a microfluidic chip quantitative sample adding device, which has the following beneficial effects:

1. The setting of the overflow pool, set the overflow pool around the sample addition pool higher than the sample addition pool, based on the full liquid of the sample addition pool as the quantitative basis, without relying on the peripheral equipment to add samples, from the time when the sample addition pool is full to the stop of adding liquid. The extra liquid added during the sampling process overflows directly into the overflow pool. The complex and expensive quantitative sample addition equipment is replaced by a very simple structure, and the method can also be extended to other platforms that require quantitative sample addition.

2. The setting of the hydrophobic gas-permeable membrane, the microfluidic chip used in on-site detection is small in size and limited in space. The overflow pool diameter is only 2-3 times the diameter of the sample addition pool. When the liquid overflows from the sample addition pool to the overflow pool During the process, due to the surface tension of water, there is a risk of being adsorbed to the outside of the overflow tank. Therefore, a layer of hydrophobic and breathable membrane is attached to the upper end of the overflow tank to avoid this risk, resulting in cross-contamination caused by leakage of samples and other liquids. .

3. The setting of the super absorbent material, the super absorbent material can further increase the capacity of the overflow tank to accommodate the overflow liquid without increasing the volume of the overflow tank, and can also directly replace the overflow tank under the condition of using a small amount of samples. .

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative work.

1 is a schematic cross-sectional view of the microfluidic chip sample adding cell of Example 1 provided by the present invention;

2 is a schematic cross-sectional view of the microfluidic chip sample adding cell of Example 2 provided by the present invention;

3 is a schematic cross-sectional view of the microfluidic chip sample adding cell of Example 3 provided by the present invention;

FIG. 4 is a schematic cross-sectional view of the microfluidic chip sample adding cell of Example 4 provided by the present invention.

in:

1- Add sample pool;

2 - overflow pool;

3- Hydrophobic breathable membrane;

4-water-absorbing ring body;

5-Injection microchannel;

6- reaction pool;

7- air hole;

8-Through hole.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1:

Referring to FIG. 1, an embodiment of the present invention discloses a microfluidic chip quantitative sample adding device, including a sample adding pool 1; The sample microchannel 5, the reaction tank 6 and the air hole 7 are connected; the overflow tank 2 is formed on the outside of the sample addition tank 1, and an overflow space is formed between the overflow tank 2 and the sample addition tank 1; the upper part of the sample addition tank 1 is connected with the sample addition tank 1 and Overflow channel for overflow pool 2.

The bottom surfaces of sample addition pool 1 and overflow pool 2 are flush, and the top edge of overflow pool 2 is higher than the top edge of sample addition pool 1, so that an overflow channel is formed between the top edge of sample addition pool 1 and the top edge of overflow pool 2; A water-absorbing ring body 4 is sleeved between the sample addition pool 1 and the overflow pool 2 .

The top edge of the overflow tank 2 is covered with a hydrophobic gas permeable membrane 3 .

When adding the sample, the nozzle of the sample tube is aligned with the opening above the sample adding cell 1. By squeezing the sample, the sample flows into the sample inflow channel along the longitudinal direction of the sample adding cell 1. When the sample addition tank 1 is full, the nozzle of the sample tube is removed from the sample addition tank 1. During the process, the liquid sample overflowing from the sample addition tank 1 flows out of the overflow tank 2 in the direction of the arrow in Figure 1. Because the hydrophobic gas permeable membrane 3 If the setting is set, there is no liquid sample remaining on the chip surface, and the quantitative sample addition of the sample required for in-chip detection is completed.

Example 2:

Referring to FIG. 2, an embodiment of the present invention discloses a quantitative sample adding device for a microfluidic chip, including a sample adding pool 1; The sample microchannel 5, the reaction tank 6 and the air hole 7 are connected; the overflow tank 2 is formed on the outside of the sample addition tank 1, and an overflow space is formed between the overflow tank 2 and the sample addition tank 1; the upper part of the sample addition tank 1 is connected with the sample addition tank 1 and Overflow channel for overflow pool 2.

The bottom surface of overflow tank 2 is flush with the top edge of sample addition tank 1, and the top edge of overflow tank 2 is higher than the top edge of sample addition tank 1, so that the top edge of sample addition tank 1 and the inside of overflow tank 2 form an overflow space. And the top opening of the sample addition tank 1 forms an overflow channel.

A water absorbing ring body 4 is placed on the bottom surface of the overflow tank 2 . The inner diameter of the water absorbing ring body 4 in the non-absorbing state is the same as the inner diameter of the sample adding tank 1 , and the outer diameter is the same as the inner diameter of the overflow tank 2 .

The thickness of the water-absorbing annular body 4 in the non-absorbing state is lower than the top edge of the overflow pool 2 .

In this embodiment, the structure of the overflow tank 2 is optimized. The upper opening of the sample addition tank 1 is surrounded by a layer of annular high water absorption material. When the liquid sample fills the sample addition tank 1, the liquid sample higher than the sample addition tank 1 will absorb water. The annular body 4 is absorbed, and the height of the top edge of the overflow pool 2 is higher than the thickness of the water-absorbing annular body 4, ensuring that the overflowing liquid is completely absorbed by the water-absorbing annular body 4 before it reaches the surface of the chip.

Example 3:

Referring to FIG. 3, an embodiment of the present invention discloses a quantitative sample adding device for a microfluidic chip, including a sample adding pool 1; The sample microchannel 5, the reaction tank 6 and the air hole 7 are connected; the overflow tank 2 is formed on the outside of the sample addition tank 1, and an overflow space is formed between the overflow tank 2 and the sample addition tank 1; the upper part of the sample addition tank 1 is connected with the sample addition tank 1 and Overflow channel for overflow pool 2.

The bottom surface and top edge of the sample adding pool 1 and the overflow pool 2 are flush, and the middle or upper part of the side wall of the sample adding pool 1 is provided with a plurality of through holes 8 in the same plane, and the through holes 8 form overflow channels.

A plurality of through holes 8 are arranged in the middle of the sample adding pool 1 or at one third of the opening. The through holes 8 communicate with the overflow pool 2 around the sample adding pool 1. The lower end of the overflow pool 2 is on the same level as the sample adding pool 1. The upper end is flush with the opening of the sample addition tank 1. When the liquid sample is added to the position of the through hole 8 of the sample addition tank 1, the liquid higher than the level of the through hole 8 overflows into the overflow tank 2 according to the arrow in Figure 3. The through hole 8 The position is lower than the opening of the sample adding pool 1, which ensures that no liquid sample overflows to the chip surface during the sample adding process.

Example 4:

Referring to FIG. 4 , an embodiment of the present invention discloses a quantitative sample adding device for a microfluidic chip, including a sample adding pool 1; The sample microchannel 5, the reaction tank 6 and the air hole 7 are connected; the overflow tank 2 is formed on the outside of the sample addition tank 1, and an overflow space is formed between the overflow tank 2 and the sample addition tank 1; the upper part of the sample addition tank 1 is connected with the sample addition tank 1 and Overflow channel for overflow pool 2.

A plurality of through holes 8 in the same plane are opened in the middle or upper part of the side wall of the sample adding tank 1, and the through holes 8 form an overflow channel; the bottom surface of the overflow tank 2 is flush with the bottom edge of the through hole 8, or is located in the through hole 8 Below the bottom edge of the overflow tank 2, the top edge of the overflow pool 2 is higher than the top edge of the through hole 8.

A water-absorbing ring body 4 is placed on the bottom surface of the overflow tank 2 . The inner diameter of the water-absorbing ring body 4 in the non-absorbing state is the same as the outer diameter of the sample adding tank 1 , and the outer diameter is the same as the inner diameter of the overflow tank 2 .

The thickness of the water-absorbing annular body 4 in the non-absorbing state is lower than the top edge of the overflow pool 2 .

A through hole 8 is provided in the middle of the sample addition tank 1 or at one third of the opening. The water absorption ring 4 is arranged on the periphery of the sample addition tank 1 and is close to the through hole 8. When the liquid sample is added to the sample addition tank At the position of the through hole 8 of The overflowing liquid is completely absorbed by the water absorbing ring body 4 before it reaches the surface of the chip.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant part can be referred to the description of the method.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A microfluidic chip quantitative sample adding device is characterized in that, comprising a sample adding pond (1); the top of the sample adding pond (1) is open, the bottom end is closed, and the lower part is successively connected to the microfluidic chip. The sample injection microchannel (5), the reaction tank (6) and the air hole (7) are communicated; an overflow tank (2) is formed on the outside of the sample addition tank (1), and the overflow tank (2) is connected to the sample addition tank An overflow space is formed between (1); the upper part of the sample adding pool (1) has an overflow channel connecting the sample adding pool (1) and the overflow pool (2). 2. A microfluidic chip quantitative sample adding device according to claim 1, characterized in that, the bottom surfaces of the sample adding pool (1) and the overflow pool (2) are flush, and the overflow pool ( 2) the top edge of the sample adding pool (1) is higher than the top edge, so that the overflow channel is formed between the top edge of the sample adding pool (1) and the top edge of the overflow pool (2); A water-absorbing annular body (4) is sleeved between the sample adding pool (1) and the overflow pool (2). 3. A microfluidic chip quantitative sample adding device according to claim 2, wherein the top edge of the overflow tank (2) is covered with a hydrophobic gas permeable membrane (3). 4. A microfluidic chip quantitative sample adding device according to claim 1, wherein the bottom surface of the overflow pool (2) is flush with the top edge of the sample adding pool (1), and the The top edge of the overflow pool (2) is higher than the top edge of the sample adding pool (1), so that the top edge of the sample adding pool (1) and the inside of the overflow pool (2) form the overflow space, And the top opening of the sample adding tank (1) forms the overflow channel. 5 . A microfluidic chip quantitative sample adding device according to claim 4 , wherein a water absorbing annular body ( 4 ) is placed on the bottom surface of the overflow tank ( 2 ), and the water absorbing annular body (4) The inner diameter in the non-water absorption state is consistent with the inner diameter of the sample adding pool (1), and the outer diameter is consistent with the inner diameter of the overflow pool (2). 6. A microfluidic chip quantitative sample adding device according to claim 4 or 5, characterized in that, the thickness of the water-absorbing annular body (4) in a non-water-absorbing state is lower than that of the overflow pool (2). ) top edge. 7. A microfluidic chip quantitative sample adding device according to claim 1, wherein the bottom surface and the top edge of the sample adding pool (1) and the overflow pool (2) are flush, so A plurality of through holes (8) in the same plane are opened in the middle or upper part of the side wall of the sample adding tank (1), and the through holes (8) form the overflow channel. 8. A microfluidic chip quantitative sample adding device according to claim 1, characterized in that, a plurality of through holes ( 8), the through hole (8) forms the overflow channel; the bottom surface of the overflow pool (2) is flush with the bottom edge of the through hole (8), or is located at the bottom of the through hole (8) Along the bottom, the top edge of the overflow pool (2) is higher than the top edge of the through hole (8). 9 . A microfluidic chip quantitative sample adding device according to claim 1 , wherein a water absorbing annular body ( 4 ) is placed on the bottom surface of the overflow tank ( 2 ), and the water absorbing annular body (4) The inner diameter in the non-water absorption state is the same as the outer diameter of the sample adding pool (1), and the outer diameter is the same as the inner diameter of the overflow pool (2). 10. A microfluidic chip quantitative sample adding device according to claim 1, characterized in that the thickness of the water-absorbing annular body (4) in a non-water-absorbing state is lower than the thickness of the overflow pool (2). top edge.

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