CN116099580A

CN116099580A - Microfluidic detection device

Info

Publication number: CN116099580A
Application number: CN202310195716.0A
Authority: CN
Inventors: 叶健; 陆辉; 徐荣; 丁晓麟; 朱金龙
Original assignee: Nanjing Norman Biotechnology Co ltd
Current assignee: Nanjing Norman Biotechnology Co ltd
Priority date: 2023-03-03
Filing date: 2023-03-03
Publication date: 2023-05-12

Abstract

The invention belongs to the field of microfluidic nucleic acid detection devices and the field of biological detection, and particularly relates to a microfluidic detection device. The device comprises a cover plate and a chip board; an opening for dripping the sample is formed in the cover plate, and a sealing plug is arranged on the opening; the upper part of the chip board is provided with a sample cavity, the lower part of the chip board is provided with at least one reaction cavity, the reaction cavity is internally packaged with a detection reagent, the lower part of the sample cavity is provided with a liquid inlet flow channel and is communicated with the reaction cavity, and the upper end of the sample cavity is communicated with the upper part of the reaction cavity to form an exhaust flow channel; the opening of the sample drop on the cover plate corresponds to a sample cavity arranged on the upper part of the chip plate. The invention has simple structure, convenient operation and can effectively reduce sample pollution in the nucleic acid detection process.

Description

Microfluidic detection device

Technical Field

The invention belongs to the field of microfluidic nucleic acid detection devices and the field of biological detection, and particularly relates to a microfluidic detection device.

Background

Based on innovative microfluidic molecular diagnosis technology, research and development are carried out on common multiple infectious diseases of human beings, and the self-test of diseases such as respiratory tract infection, childhood infection, genital tract infection and the like can be realized, including detection of hepatitis A and B virus, syncytial virus, rotavirus, norovirus, AIDS, syphilis, gonorrhea, pet infection and the like, and the influence of the infectious diseases on daily life and social economy of people can be reduced through rapid detection and diagnosis without extraction. Microfluidic is originally derived from microanalysis methods, including gas chromatography (GPC), high Performance Liquid Chromatography (HPLC), or Capillary Electrophoresis (CE), among others. These techniques originate in the last 50 to 60 th century and can be used to isolate or analyze compounds or biomolecules by flowing small amounts of samples into narrow test tubes or capillaries, thereby achieving high sensitivity and resolution. Early in the 1980 s PCRKary Mullis developed an important thrust for the research of microfluidic technology by DNA polymerase chain reaction technology.

Microfluidic is a scientific technology with accurate control and manipulation of microscale fluids, which is characterized by manipulating fluids in a micro-nano scale space, and has the capability of reducing basic functions of laboratories such as biology, chemistry, etc. such as sample preparation, reaction, separation, detection, etc. to a few square centimeters chip, and the basic features and the greatest advantages are flexible combination and scale integration of various unit technologies on an integrally controllable micro platform. Microfluidic technology uses tubing on the scale of tens to hundreds of microns to process or manipulate very small amounts (on the order of cubic millimeters to cubic microns) of fluid. The original microfluidic technology is used for analysis, and has the advantages of high-precision and high-sensitivity separation and detection by using very few samples and reagents, low cost, short analysis time, small imprint of analysis equipment and the like. The most obvious features of microfluidic technology, namely small size, are also the features of less obvious microchannel fluid. It essentially provides the ability to control molecules centrally in space and time, an emerging interdisciplinary discipline involving chemical, fluid physics, microelectronics, new materials, biology and biomedical engineering. The method can integrate basic units of preparation, reaction, separation, detection and the like into a micron-scale chip in the process of analyzing samples in the fields of biology, chemistry, medicine and the like, and automatically complete the whole analysis process.

The micro-fluidic technology can concentrate the whole process of detecting the nucleic acid sample on a chip of a few centimeters, and the operation process of detecting is comprehensively completed through the design of a liquid flow channel, the arrangement of a micro valve, the design of a liquid cavity and other modules, so that the whole detection is miniaturized. When the DNA polymerase chain reaction technology is used, under the important development trend of increasing miniaturization of a microfluidic detection device, the problem of bubbles becomes a big obstacle for influencing the detection result of nucleic acid, such as bubbles introduced when a medium or a liquid drop is added into the microfluidic device, bubbles dissolved in a filling medium or the liquid drop, bubbles generated by heating at a high temperature experiment, expansion of the bubbles and the like, if the bubbles expand or shrink when moving on the microfluidic device or are blocked at a certain position of a driving path, the manipulation of the liquid drop can be blocked, the driving stability is damaged, and the serious cases can damage the modification properties or the coating structure of the surfaces of upper and lower plates of the microfluidic chip; in addition, when detecting nucleic acid in a droplet, the presence of bubbles can greatly interfere with the detection result. The existing microfluidic detection device discharges bubbles possibly existing in the injection hole and the flow path by arranging the exhaust hole and the injection hole which are respectively positioned at the two ends of the flow path, but the structure makes the design of the device complex, and simultaneously increases the volume of the device.

Disclosure of Invention

In order to solve the technical problems, the invention provides a microfluidic detection device which can solve the problems of larger volume, complex product structure, inconvenient operation, low detection accuracy and the like of the traditional device.

The microfluidic detection device comprises a cover plate and a chip plate; an opening for dripping the sample is formed in the cover plate, and a sealing plug is arranged on the opening; the upper part of the chip board is provided with a sample cavity, the lower part of the chip board is provided with at least one reaction cavity, and a detection reagent is packaged in the reaction cavity; the lower part of the sample cavity is provided with a liquid inlet flow channel, the tail end of the liquid inlet flow channel is provided with branches and communicated with all the reaction cavities, the upper parts of all the reaction cavities are provided with exhaust flow channels, the top ends of the exhaust flow channels are communicated with the upper ends of the sample cavities, and the liquid inlet flow channel and the exhaust flow channel are communicated with the reaction cavities through the sample cavities; the opening of the sample drop on the cover plate corresponds to a sample cavity arranged on the upper part of the chip plate.

Preferably, one end of the liquid inlet channel is obliquely cut into the connecting reaction cavity from top to bottom; one end of the exhaust runner is connected to the top end of the sample cavity, and the other end of the exhaust runner is connected to the top end of the reaction cavity.

Preferably, the reaction cavity is of a special-shaped design, and the top end of the reaction cavity is provided with a contraction part.

Preferably, the bottom of the chip board is also provided with a bottom sheet, and the cover sheet, the chip board and the bottom sheet are tightly fixedly connected; the liquid inlet flow channel and the exhaust flow channel are respectively arranged on two sides of the chip board.

Preferably, the exhaust runner is arranged on the front surface of the chip board, and the liquid inlet runner is arranged on the back surface of the chip board.

Preferably, a filtering part is arranged on the bottom sheet.

Preferably, the filtering parts on the bottom sheet are a plurality of rows of columns.

Preferably, a blocking part is arranged on the bottom plate corresponding to the sample cavity and the opening.

Preferably, the bottom plate or the baffle component is provided with a convex part corresponding to the opening.

Preferably, the sealing plug is provided with an annular groove, the opening is correspondingly provided with an annular bulge, and the annular bulge is buckled with the annular groove.

Preferably, the sealing plug is integrally injection molded with the cover plate or the chip board through the connecting piece.

Preferably, the cover plate, the chip plate and the cover plate are formed by injection molding, and the bonding mode is adhesive bonding, ultrasonic welding, laser welding or thermal bonding.

Preferably, the reaction chamber is filled with freeze-dried spheres for detection reagents.

According to the microfluidic detection device, through the design of the opening and the communication of the sample cavity, the liquid inlet flow channel, the reaction cavity and the exhaust flow channel, the emission of bubbles, waste gas and the like is realized, the sample pollution caused by the additional arrangement of the exhaust holes is avoided, and the problems of complex structure, inconvenient operation, low detection accuracy and the like of the existing nucleic acid detection product can be solved.

Drawings

FIG. 1 is a schematic view of an inlet flow path of a microfluidic detection device according to the present invention;

FIG. 2 is a schematic diagram of an exhaust flow channel of a microfluidic detection device according to the present invention;

FIG. 3 is an exploded view of one embodiment of the present invention;

FIG. 4 is an enlarged view of a portion of a reaction chamber according to the present invention;

FIG. 5 is an exploded view of the front structure of a second embodiment of the present invention;

FIG. 6 is an exploded view of the rear structure of a second embodiment of the present invention;

FIG. 7 is an exploded view of a third embodiment of the present invention;

FIG. 8 is an enlarged view of a portion of the filter according to the present invention;

FIG. 9 is a schematic diagram of a microfluidic detection device according to the present invention;

fig. 10 is a perspective view of a microfluidic detection device according to the present invention.

Wherein: 1-cover plate; 2-chip board; 3-opening; 31-annular protrusions; 4-sealing plugs; 41-an annular groove; 42-connecting piece; 5-sample chamber; 6-a reaction chamber; 7-a liquid inlet flow channel; 8-an exhaust runner; 9-a lysate tube; 10-freeze-drying the balls; 11-a backsheet; a 111 gear member; 112 raised portions; 12 filtration sections.

Detailed Description

The following describes the preferred technical scheme of the invention further with reference to the attached drawings and the specific embodiments.

As shown in fig. 1-3, the invention provides a microfluidic detection device, which comprises a cover plate 1 and a chip board 2, wherein an opening 3 for dripping samples is formed in the cover plate 1, and a sealing plug 4 is arranged on the opening 3 for sealing; the upper portion of the chip board 2 is provided with a sample cavity 5, the lower portion is provided with at least one reaction cavity 6, a detection reagent is packaged in the reaction cavity, the lower portion of the sample cavity is provided with a liquid inlet flow channel 7 and is communicated with the reaction cavity 6, and meanwhile, the sample cavity is provided with an exhaust flow channel 8 and is communicated with the upper portion of the reaction cavity 6. Referring to fig. 2, when two reaction chambers 6 are disposed on the chip board 2, the tail ends of the liquid inlet channels disposed at the lower portion of the sample chamber 5 are branched and are respectively communicated with the two reaction chambers, the upper portions of the two reaction chambers are respectively provided with an exhaust channel 8, the top ends of the two exhaust channels are respectively communicated with the upper ends of the sample chambers, and the liquid inlet channels and the exhaust channels are communicated with the reaction chambers through the sample chambers. At this time, the sample is dropped into the sample chamber 5 through the opening 3 and flows into the reaction chamber by itself through the liquid inlet channel 7 under the action of capillary and gravity, and the sample position and the reaction chamber form a large height drop due to the vertical arrangement of the device, so that the sample can fill the reaction chamber in a relatively fast time. At this time, if bubbles or reaction gas are present in the liquid inlet flow channel and the reaction chamber, the bubbles or reaction gas can float upwards to pass through the upper part of the reaction chamber and communicate with the air outlet flow channel 8 to enter the space at the upper part of the sample chamber 5. The microfluidic detection device provided by the invention has the advantages that the sample dripping is realized only through one opening 3, and meanwhile, the discharge of bubbles, waste gas and the like is realized through the communication of the sample cavity, the liquid inlet flow channel and the air outlet flow channel, so that the sample pollution caused by the additional arrangement of the air outlet holes is avoided, and the volume of the device can be effectively reduced.

One end of the liquid inlet channel is obliquely cut into the connecting reaction cavity from top to bottom; one end of the exhaust runner is connected to the top end of the sample cavity, and the other end of the exhaust runner is connected to the top end of the reaction cavity. One end of the liquid inlet channel is obliquely cut into the connecting reaction cavity from top to bottom, so that the sample liquid can conveniently flow into the reaction cavity, and meanwhile, the liquid in the reaction cavity is prevented from flowing into the liquid inlet channel reversely. The exhaust runner is connected at sample chamber and reaction chamber top respectively and can make gaseous or bubble come-up, removes to sample chamber upper end from the reaction chamber, reduces the interior sour detection sample of reaction chamber and pollutes and testing result, and gaseous or bubble is discharged into sample chamber top simultaneously, can not influence sample chamber bottom sample and flow into the runner. Further, as shown in fig. 4, the reaction chamber is of a special-shaped design, and the top end of the reaction chamber is provided with a contraction part, so that a space for accommodating bubbles is reserved, and even if micro bubbles are generated, the detection is not affected.

Referring to fig. 3 of the present embodiment, a bottom plate 11 is disposed at the bottom of the chip plate 2, and the cover plate 1, the chip plate 2 and the bottom plate 11 are tightly fixed to each other, so that the sample liquid, the waste gas, etc. can only pass through the sample cavity, the reaction cavity, the liquid inlet channel and the air outlet channel. The cover plate 1, the chip plate 2 and the bottom plate 11 are formed by injection molding, and the bonding mode adopts gluing, ultrasonic welding, laser welding, thermal bonding and the like, so that the cover plate 1, the chip plate 2 and the bottom plate 11 are tightly attached. The liquid inlet flow channel 7 and the air outlet flow channel 8 of the chip board are respectively arranged on the two sides of the chip board 2 so as to ensure the smoothness of liquid inlet and air outlet; the exhaust runner is located the front of chip board, and the front is up, has not only guaranteed that the application of sample liquid can not block up the exhaust runner at first, and furthest has guaranteed that the distance of inlet and gas vent is furthest moreover, reduces the possibility of forming great bubble in the reaction chamber to minimum.

The baffle member 111 is disposed on the bottom plate 11 corresponding to the sample cavity 5 and the opening 3, the baffle member 111 is disposed in a semi-annular shape corresponding to the upper portion of the opening 3, when the sample drops into the sample cavity, the sample liquid flows from the baffle member 111 to the lower end of the chip board due to the baffle of the baffle member 111, and can be prevented from flowing to the top end of the sample cavity as much as possible, so as to provide a space for collecting waste gas or bubbles for the upper portion of the sample cavity. Further, the bottom plate 11 or the blocking member 111 is provided with a protruding portion 112 corresponding to the opening 3, the protruding portion 112 is higher than the plane of the bottom plate 11, when the lysate pipe 9 is inserted into the opening to drop the sample, the plane of the opening of the lysate pipe is prevented from being flush with the plane of the bottom plate, and the sample liquid cannot flow out.

As shown in fig. 5-6, in the embodiment of the invention when the number of reaction chambers is 6, the number of liquid inlet channels 7 and the number of air outlet channels 8 are respectively 6, so as to save the space of the chip board to the greatest extent and facilitate the flow passage, and the liquid inlet channels 7 and the air outlet channels 8 are respectively arranged on two sides of the chip board. Meanwhile, the flow channels can not be crossed, so that the flow channel circulation can be ensured to the greatest extent.

As shown in fig. 7-8, in the embodiment where the bottom plate 11 includes the filtering portion 12, the filtering portion 12 is disposed at the lower end of the blocking member 111, and is formed by a plurality of rows of columns with certain gaps, where the columns may be cylinders, cones or truncated cones, and the columns of the front row and the rear row are staggered, so as to filter larger foreign matters in the liquid sample, such as a swab for dropping the batting, etc.

Optionally, the sealing plug 4 is integrally injection molded with the cover plate 1 or the chip board 2 through the connecting piece 42, so that the sealing plug 4 is connected to the device of the invention, thereby avoiding loss and inconvenient use. Further, as shown in fig. 9-10, the sealing plug 4 is provided with an annular groove 41, the opening 3 is correspondingly provided with an annular protrusion 31 (or the sealing plug 4 is provided with an annular protrusion, the opening 3 is correspondingly provided with an annular groove), after the sample in the lysate pipe 9 drops into the sample cavity, the sealing plug cannot be opened after being buckled with the opening through the buckling of the annular groove and the annular protrusion, so that the sample pollution is avoided, and the accuracy of the detection result is ensured.

Preferably, the reaction chamber is filled with the detection reagent by freeze-dried balls 10. Fig. 1 shows a double reaction chamber device, and the ball placement scheme has 3 kinds: a. one reaction chamber is provided with a reagent ball for detecting a certain virus nucleic acid, and the other reaction chamber is provided with an internal reference reagent ball for checking the validity of a sample; b. the reagent balls for detecting a certain virus nucleic acid are placed in the two reaction chambers, so that the detection accuracy can be improved to a great extent; c. two reagent balls for detecting different virus nucleic acids are respectively placed in the two reaction chambers, so that the screening range can be greatly enlarged.

The microfluidic detection device is convenient to operate, when the microfluidic detection device is used, a sample is dripped through the opening of the cover plate, then the sealing plug is buckled, and the sealing plug is prevented from being opened manually through buckling the sealing plug and the opening, so that the sample is kept in a pollution-free state once the sample is added. Secondly, the device is erected on nucleic acid detection equipment, and as the baffle part is arranged on the bottom plate corresponding to the sample cavity and the opening, the sample can exist at the lower end of the baffle part of the sample cavity and flow downwards, so that the sample is prevented from being dispersed in the whole sample cavity, a gas storage space is reserved for the upper part of the sample cavity, and the drainage function of flowing the sample to the lower liquid inlet channel is also realized; the convex parts are arranged at the positions corresponding to the openings on the bottom plate or the baffle component, so that the pipe orifice is not directly contacted with the bottom plate in a plane when the lysate pipe stretches into the sample cavity to add the sample, and the smoothness and the speed of the sample adding are effectively increased; a plurality of rows of columnar filtering parts are arranged at the lower end of the bottom plate and are used for filtering larger foreign matters in the liquid sample. Then, the device is erected on the detection equipment, a sample enters the reaction cavity through the liquid inlet channel and reacts with the nucleic acid detection reagent, and bubbles or gas in the liquid inlet channel and the reaction cavity enter the top end of the sample cavity through the gas outlet channel at the top end of the reaction cavity, so that the upper part of the sample cavity is gas, and the lower part of the sample cavity is the sample flowing to the liquid inlet channel.

The device has good experience, only one sample is needed, and during sample adding, all the sample is extruded into the inlet, so that the number of sample adding drops is not needed to be accurately controlled; after the sample is added, the sealing plug can be covered without waiting for the sample to fill the reaction cavity; the device with the sealing plug can be put into an instrument for incubation detection, and the reaction cavity is not required to be filled with a sample. Simple structure, convenient operation and difficult being polluted when the sample is detected, and the accuracy of the nucleic acid detection result is improved.

The technical features of the above embodiments may be arbitrarily combined, and for brevity, all of the possible combinations of the technical features of the above embodiments are not described; the scope of the present specification should be considered as long as there is no contradiction between the combinations of these technical features.

Claims

1. The microfluidic detection device is characterized by comprising a cover plate and a chip board; an opening for dripping the sample is formed in the cover plate, and a sealing plug is arranged on the opening; the upper part of the chip board is provided with a sample cavity, the lower part of the chip board is provided with at least one reaction cavity, and a detection reagent is packaged in the reaction cavity; the lower part of the sample cavity is provided with a liquid inlet flow channel, the tail end of the liquid inlet flow channel is provided with branches and communicated with all the reaction cavities, the upper parts of all the reaction cavities are provided with exhaust flow channels, the top ends of the exhaust flow channels are communicated with the upper ends of the sample cavities, and the liquid inlet flow channel and the exhaust flow channel are communicated with the reaction cavities through the sample cavities; the opening of the sample drop on the cover plate corresponds to a sample cavity arranged on the upper part of the chip plate.

2. The microfluidic detection device according to claim 1, wherein one end of the liquid inlet channel is beveled into the connection reaction chamber from top to bottom; one end of the exhaust runner is connected to the top end of the sample cavity, and the other end of the exhaust runner is connected to the top end of the reaction cavity.

3. The microfluidic detection device according to claim 1, wherein the reaction chamber is of a profiled design with a constriction at the top end.

4. The microfluidic detection device according to claim 1, wherein a bottom plate is further arranged at the bottom of the chip plate, and the cover plate, the chip plate and the bottom plate are tightly fixedly connected; the liquid inlet flow channel and the exhaust flow channel are respectively arranged on two sides of the chip board.

5. The microfluidic detection device according to claim 4, wherein the exhaust flow channel is disposed on a front side of the chip board and the inlet flow channel is disposed on a back side of the chip board.

6. The microfluidic detection device according to claim 4, wherein a filter is provided on the bottom sheet.

7. The microfluidic detection device according to claim 6, wherein the filtration portions on the bottom sheet are a plurality of rows of columns.

8. The microfluidic detection device according to claim 4, wherein a blocking member is disposed on the bottom plate corresponding to the sample chamber and the opening.

9. The microfluidic detection device according to claim 8, wherein a protrusion is provided on the backsheet or the blocking member at a position corresponding to the opening.

10. The microfluidic detection device according to claim 1, wherein the sealing plug is provided with an annular groove, and the opening is provided with an annular protrusion, and the annular groove is buckled with the annular protrusion.

11. The microfluidic detection device according to claim 1, wherein the sealing plug is injection molded integrally with the cover plate or chip plate via a connector.

12. The microfluidic device of claim 4, wherein the cover sheet, the chip board and the bottom sheet are injection molded, and the bonding means is adhesive, ultrasonic welding, laser welding or thermal bonding.

13. The microfluidic detection device according to claim 1 or 4, wherein the reaction chamber encloses a lyophilized pellet for detection reagent.