CN109030369B - A multi-channel microfluidic chip used in conjunction with cuvettes - Google Patents

Abstract

The invention provides a method for using a microfluidic chip used in combination with a cuvette, which consists of three parts: a flow diversion area, a mixing area and a liquid outlet area. It is characterized in that: the whole chip is in the shape of a cuboid slab. Arrange vertically according to the long side of the cuboid, and process various functional components of the diversion area, mixing area, and liquid outlet area sequentially from the top. The invention solves the functional integration of sample injection, splitting, reagent addition and mixing in the pretreatment of heavy metal samples, and provides a multi-channel microfluidic chip for heavy metal ion detection. The beneficial effects of the present invention are: uniform flow distribution, rapid solution mixing, unique and durable liquid outlet interface; it can be directly connected with different types of cuvettes; Read parameter data.

Description

A multi-channel microfluidic chip used in conjunction with cuvettes

technical field

The invention relates to a multi-channel microfluidic chip, in particular to a multi-channel microfluidic chip which is used for detecting heavy metal ions and can be directly used in combination with cuvettes of various specifications.

technical background

At present, with the rapid development of various industries and manufacturing industries, the widespread use of pesticides and chemical fertilizers, the pollution of heavy metals in farmland and rivers is becoming more and more serious. Because of their toxicity, heavy metal pollution is easy to accumulate in plants, animals and humans through the food chain. It poses a serious threat to the ecological environment and human health, and has attracted more and more attention. Therefore, in order to make the detection of heavy metals simple and cheap, a simple, practicable, and low reagent consumption test device becomes an urgent need.

Microfluidic chips, also known as lab-on-a-chip or micro-total analysis systems, use micro-processing technology to perform basic sample pretreatment, reaction, separation, and detection in chemistry, and cell culture, sorting, and lysis in life sciences. The operating unit is integrated on a chip with a size of several square centimeters, and the microchannel network is used to flexibly control the entire experimental system, thereby realizing various functions of traditional chemical or biological laboratories. Since it was first proposed in the early 1990s, microfluidic chips have been widely used in analytical chemistry, synthetic chemistry, drug screening, and clinical diagnosis due to the advantages of fast analysis speed, low reagent consumption, miniaturization, integration, and automation. , biotechnology, environmental testing and other fields.

At present, heavy metal ion detection equipment is generally based on large-scale devices, which have many limitations. If there is a small device that can detect heavy metal ions, and a low-cost detection tool, it will fill this gap.

Contents of the invention

The present invention provides a multi-channel microfluidic chip for the detection of heavy metal ions in order to solve the difficulties in the pretreatment of heavy metal samples, such as sampling, splitting, adding reagents, mixing and collecting operations, and the shortcomings of quantitative analysis. A functionally integrated device.

The technical solution of the present invention is that a multi-channel microfluidic chip used in conjunction with a cuvette is composed of three parts: a flow diversion area, a mixing area, and a liquid outlet area. It is characterized in that: the whole chip is in the shape of a cuboid slab. Arranged vertically according to the longest side of the cuboid, and sequentially process various functional components of the diversion area, mixing area, and liquid outlet area from the top.

The split flow area includes a sample inlet at the top, a cylindrical sample storage tank below the sample inlet, and a main channel communicated with the bottom of the sample storage tank, and also includes a liquid separation port and a sample separation channel. The main channel is connected to three sample-dividing channels through the liquid-dispensing port, and the three sample-dividing channels are arranged parallel, vertically and equidistantly after the liquid is separated by the liquid-distributing port. The width dimension of the liquid distribution port is consistent with the width of the main channel, and the channel depth dimension of the liquid distribution port is smaller than the depth dimension of the main channel. One split bar and two small split bars, or one split island, are processed in the channel of the liquid split port. Two triangular liquid separation sharp corners are processed between the three sample distribution channel openings of the liquid distribution port, that is, between the two side sample distribution channel openings and one middle sample distribution channel opening.

The mixing zone includes a cylindrical valve chamber in which each sample-dividing channel is processed horizontally on the same horizontal plane, a liquid collecting port at the bottom outlet of the valve chamber, and a liquid homogenizing chamber below the liquid collecting port. The valve cavity is processed in cooperation with the valve body. The valve body is a cylinder and can rotate in a closed manner in the valve chamber. The inside of the valve body is a hollow bottle-like structure, the top sealing cover is processed into a fixed knob, and a reagent opening and closing port is processed at the center of the knob. A through square hole is processed on the side wall of the middle part of the valve body. The size of the square hole is consistent with the size of the interface between the sample distribution channel and the valve chamber, and is correspondingly consistent with the size of the valve chamber and the liquid collecting port. The liquid gathering port is a frustum-shaped through channel with a large upper part and a smaller lower part, and the liquid equalization chamber communicates with it below. The liquid equalization chamber is composed of a cavity and a hemisphere, and the hemisphere is suspended at the lower part of the liquid equalization chamber by a supporting frame. Directly above the hemisphere of the homogenizing chamber is the processing position of the liquid collecting port. The size of the lower outlet of the liquid collecting port can be adjusted to ensure that the liquid flowing out of the valve body drops on the hemisphere of the liquid homogenizing chamber in the form of droplets.

The liquid outlet area is composed of a collection pool and a retractable liquid outlet interface. The collection tank is under the liquid equalization chamber, communicates with the liquid equalization chamber, and collects and stores the mixed liquid droplets passing through the hemisphere of the liquid equalization chamber. The liquid outlet interface is a retractable interface, and slide rails are processed on both sides of the liquid outlet interface for connection with cuvettes. A handle for controlling the telescopic liquid outlet interface is also processed in the liquid outlet area at the lower part of the chip. The bottom of the chip is matched with a sealing bottom cover that seals the entire bottom surface of the chip.

Preferably in the above technical solution, each of the sample dividing channels can be combined with the liquid distribution port, and continue to be divided into three sample dividing channels, that is, one chip can be divided into 9 sample dividing channels, and connected to the functional components below the sampling channel Uniform one-to-one corresponding increase, can form 9 kinds of mixed solutions, connected to 9 cuvettes. Both the main channel and the sampling channel are treated with hydrophobic surface by plasma treatment. Both the cavity and the hemisphere in the mixing zone are treated with a hydrophobic surface.

In the above technical solution, preferably, the splitter column is on the centerline of the channel of the liquid distribution port; two small splitter columns are arranged on both sides of the rear part. The diversion island is in the shape of a shuttle, and the tip of the diversion island at the front and the tail tip of the island at the tail are both on the center line of the channel of the liquid distribution port. The middle rear part of the diversion island is processed into a concave shape in the middle at the openings facing the sample distribution channels on both sides.

Preferably in the above technical solution, the size of the outlet of the lower part of the liquid collecting port can be adjusted by the drip beads put into the liquid collecting port with different diameters, and the dripping beads in each liquid collecting port are prevented by a protective screen. Drop out and replace.

The above technical solutions of the present invention mainly have the following beneficial effects.

(1) Uniform flow distribution. The design of the liquid separation port divides the reagent passing through the main pipeline into three parts evenly through the vertices of the two triangles, and enters the three injection channels respectively.

(2) The solution is mixed rapidly. The design of the liquid collecting port can drop the mixed liquid in the valve in the form of water droplets, controlling the reaction rate of the entire device. Dropping the mixed solution on the hemisphere in the form of water droplets at intervals can ensure that the mixed solution forms countless finer water droplets, and after mixing these water droplets, a fully mixed solution can be obtained. And the entire mixing zone is coated with hydrophobic material to avoid surface solution adhesion.

(3) Unique liquid outlet interface. The liquid outlet interface is designed to be similar to the Type-C interface commonly used in current mobile phones, so that the liquid outlet interface can be directly connected to the cuvette, and different reagents are mixed by the chip and directly flow into the cuvette, eliminating the need for transfer steps. Minimize the waste of reagents. In addition, the design of slide rails is added to both ends of the liquid outlet interface. When idle, the liquid outlet interface is retracted into the chip and covered with a cover, which can effectively avoid contact with the outside world and cause pollution.

Description of drawings

Fig. 1 is a schematic diagram of a front view structure of the present invention.

Fig. 2 is a schematic diagram of a right-view structure of the present invention.

Fig. 3 is a front view and a right view structural schematic diagram of a valve body of the present invention.

Fig. 4 is a schematic diagram of the present invention assembled and used with a cuvette.

Fig. 5 is a schematic plan view of a homogeneous liquid chamber of the present invention.

Fig. 6 is a structural schematic diagram of a liquid distribution port of the present invention.

Fig. 7 is a schematic cross-sectional view of a liquid distribution port of the present invention.

Fig. 8 is a schematic top view structural view of a diversion island of the present invention.

Fig. 9 is a schematic front view structural view of a liquid collecting port of the present invention.

In the figure: 1. Sample inlet; 2. Storage tank; 3. Main channel; 4. Liquid distribution port; 5. Sample distribution channel; 6. Valve cavity; .Support frame; 10. Slide rail; 11. Collection pool; 12. Handle; 13. Outlet interface; 14. Square hole; 15. Valve body; 16. Reagent opening and closing port; 17. Knob; 18. Sealing bottom cover; 19. Cuvette; 20. Convex liquid head; 21. Split column; 22. Small split column; 23. Separation sharp corner; 24. Middle sample channel; 25. Both sides sample channel; 27. Distributor island; 28. Concave surface in the middle; 29. Island tip; 30. Chip holder; 31. Droplet; 32. Protective mesh.

specific embodiment

Referring to the shape and structure of Fig. 1 and Fig. 9, a multi-channel microfluidic chip used in conjunction with a cuvette is composed of three parts: a flow diversion area, a mixing area, and a liquid outlet area. It is characterized in that: the whole chip is in the shape of a cuboid slab. Place vertically according to the longest side of the cuboid, fix it with a chip holder 30, and sequentially process various functional parts of the diversion area, the mixing area, and the liquid outlet area from the top.

The split area includes the top sample inlet 1 , the cylindrical sample storage tank 2 below the sample inlet 1 , and the main channel 3 communicating with the sample storage tank 2 , and also includes a liquid separation port 4 and a sample separation channel 5 . The main channel 3 is connected to three sample distribution channels 5 through the liquid distribution port 4, and the three sample distribution channels 5 are arranged parallel, vertical and equidistant after liquid separation at the liquid distribution port 4. The width dimension of the liquid distribution port 4 is consistent with the width of the main channel 3, and the channel depth dimension of the liquid distribution port 4 is smaller than the depth dimension of the main channel 3. This design is that the speed of the liquid is changed at the liquid distribution port 4, which is beneficial to diversion. One split column 21 and two small split columns 22 or one split island 27 are processed in the channel of the liquid split port 4 . Two triangular liquid-distributing corners 23 are processed between the 5 openings of the 3 sample-dividing channels of the liquid-dispensing port 4 , that is, between the 2 side-side sample-dividing channels 25 and the middle sample-dividing channel 24 . The design of the splitting functional parts of the liquid splitting port 4 is to accurately and evenly split the sample liquid in the main channel 3 under a constant sample flow rate or a steady acceleration state according to the optimal size parameters simulated by the computer. The sample liquid passes through the two triangular splitting corners 23, divides the sample liquid passing through the main channel 3 into three parts, and enters the three sample dividing channels 5 respectively.

The mixing zone includes a cylindrical valve chamber 6 horizontally processed on the same horizontal plane for each sampling channel 5 , a liquid collecting port 7 at the bottom outlet of the valve chamber 6 , and a liquid homogenizing chamber 8 below the liquid collecting port 7 . The valve cavity 6 is co-processed with the valve body 15; the valve body 15 is a cylinder and can rotate in the valve cavity 6 in a closed manner. The inside of the valve body 15 is a hollow bottle-like structure, the top sealing cap is processed into a fixed knob 17, and a reagent opening and closing port 16 is processed at the center of the knob 17. A through square hole 14 is processed on the side wall of the middle part of the valve body 15. The size of the square hole 14 is consistent with the size of the interface between the sample distribution channel 5 and the valve cavity 6, and corresponds to the size of the valve cavity 6 and the liquid collecting port 7. Consistent, same size. The reagent opening and closing port 16 is located on the top of the whole valve body, and is mainly used for adding heavy metal ion solution, and other reagent solutions can also be added according to the detection requirements. The square hole 14 is a square hole opened on the side of the valve body 15, and its main function is to connect the inside of the valve body 15 with the sampling channel 5 and the liquid collecting port 7. Because the whole valve body 15 has only one square hole, so when the square hole is not aligned with the sample distribution channel 5, a section of the sample distribution channel 5 will be closed, there will be a part of gas, and the solution cannot flow down. The inside of the whole valve body 15 is a hollow structure, so there is a certain volume, which can temporarily store the solution entering the valve body 15 through the sample inlet 1 and the sample dividing channel 5 . The liquid collecting port 7 is a frustum-shaped through channel with a large upper part and a smaller lower part, and the liquid equalization chamber 8 communicates with it below. The liquid equalization chamber 8 is composed of a cavity and a hemisphere, and the hemisphere is supported on the lower part of the liquid equalization chamber 8 by a supporting frame 9 . Directly above the hemisphere of the liquid equalizing chamber 8 is the processing position of the liquid collecting port 7. The size of the outlet of the lower part of the liquid collecting port 7 can be adjusted to ensure that the liquid flowing out of the valve body 15 drops on the liquid equalizing chamber 8 hemisphere in the form of droplets. physically. The main components of the uniform liquid chamber 8 are a hemisphere, a support frame 9 and a cuboid cavity, wherein the function of the hemisphere is to make droplets splash, and the function of the support frame 9 is to support the hemisphere. The design of the liquid-gathering port 7 can drip the mixed liquid in the valve body 15 in the form of water droplets, which controls the reaction rate of the entire device. Dropping the mixed solution in the form of water droplets on the hemisphere of the homogenizing chamber 8 at intervals can ensure that the mixed solution forms countless finer water droplets, and a fully mixed solution can be obtained after these water droplets are mixed. And the entire mixing zone is coated with hydrophobic material to avoid surface solution adhesion. The position of the mixing zone is in the middle and lower part of the whole chip, and the upper section of the collection pool 11 and the liquid outlet interface 13 .

The liquid outlet area is composed of a collection pool 11 and a retractable liquid outlet interface 13 . The collection tank 11 is located below the liquid equalization chamber 8 and communicates with the liquid equalization chamber 8 to collect and store the mixed liquid droplets passing through the hemisphere of the liquid equalization chamber 8 . The liquid outlet interface 13 is a retractable interface, and slide rails 10 are processed on both sides of the liquid outlet interface 13 for connecting with the cuvette 19 . A handle 12 for controlling the telescopic liquid outlet interface 13 is also processed in the liquid outlet area at the lower part of the chip. The bottom of the chip is matched with a sealing bottom cover 18 that seals the entire bottom surface of the chip. The liquid outlet interface 13 is designed to be similar to the Type-C interface commonly used in current electronic products, so that the liquid outlet interface 13 can be directly connected to the cuvette 19, and different reagents are mixed through the chip, and directly flow into the cuvette 19 after reaction , saves the step of transfer, and minimizes the waste of reagents. And the design of slide rails is added at both ends of the liquid outlet interface 13, and the liquid outlet interface 13 is retracted into the chip when idle, and covered with a sealed bottom cover 18, which can effectively avoid contact with the outside world to cause pollution. The sealing bottom cover 18 is used to cover the bottom of the chip to avoid contamination of the liquid outlet interface 13 . Because the liquid outlet interface 13 is designed to be retractable, the liquid outlet interface 13 needs to be retracted after use, and then the sealing bottom cover 18 is covered to seal the chip mixing area.

In the present invention, three specific detection reagents for heavy metals are added to the three valve bodies 15, and the sample liquid to be measured for heavy metal ions is added to the sample inlet 1, so that the heavy metal detection experiment can be completed. The invention solves the functional integration of the heavy metal sample pretreatment device in sample injection, flow splitting, reagent addition and mixing, and provides a multi-channel microfluidic chip for heavy metal ion detection. At the same time, the present invention adds three kinds of heavy metal ion reagents with a certain concentration to the three valve bodies 15, and adds living cell suspension to the injection port 1, which can also be used to complete the cytotoxicity experiment. For live cell toxicity experiments, the chip of the present invention is more suitable for live cell toxicity experiments with high toxicity or high concentration of heavy metal ions.

In the above-mentioned technical scheme, each of the sampling channels 5 can be combined with the liquid distribution port 4, and then divided into three sampling channels 5, that is, one chip can be divided into 9 sampling channels 5, and connected to the sampling channels 5. The following functional parts are increased one by one, which can mix 9 kinds of reagents and connect 9 cuvettes. Both the main channel 3 and the sampling channel 5 are treated with hydrophobic surface by plasma treatment. Both the cavity and the hemisphere in the mixing zone are treated with a hydrophobic surface. Example: polytetrafluoroethylene (PTFE) coating.

In the above technical solution, the splitter column 21 divides the convex liquid head 20 into two parts on the center line of the channel of the liquid distribution port 4 . 2 small shunt columns 22 are listed on both sides of its rear portion. The diversion island 27 is in the shape of a shuttle, and the diversion island point 26 at the front and the island tail point 29 at the tail are all on the center line of the channel of the liquid distribution port 4 . The middle and rear part of the flow-distributing island 27 is processed into a central concave surface 28 at the openings facing the sample distribution channels 25 on both sides. The role of the concave surface 28 in the middle is to introduce the divided liquid into the middle sample-dividing channel 24 .

In the above technical solution, the size of the outlet of the lower part of the liquid-gathering port 7 can be adjusted with the drip beads 31 put into the liquid-gathering port 7 with different diameters, and the drip beads 31 in each liquid-gathering port 7 Prevent falling out and changing with protective net plate 32.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.

Claims (4)

1. A multi-channel microfluidic chip used in conjunction with a cuvette is composed of three parts: a shunt area, a mixing area, and a liquid outlet area; The longest side is placed vertically, and each functional part of the diversion area, mixing area, and liquid outlet area is sequentially processed from the top; The split area includes the top sample inlet, the cylindrical sample storage tank below the sample inlet, and the main channel communicated with the sample storage tank below, and also includes a liquid separation port and a sampling channel; the main channel passes through the liquid separation port Connect 3 sample-dividing channels, and the 3 sample-dividing channels are arranged in a parallel vertical equidistant manner after the liquid distribution port; the width of the liquid distribution port is consistent with the width of the main channel, and the channel depth of the liquid distribution port is smaller than the main Channel depth dimension; 1 split bar and 2 small split bars, or 1 split island, are processed in the channel of the liquid split port; Two triangular liquid separation sharp corners are processed between the two side sample distribution channels and one middle sample distribution channel; The mixing zone includes each sample-dividing passage on the same horizontal plane, a horizontally processed cylindrical valve cavity, and a liquid collecting port at the bottom outlet of the valve cavity, and an even liquid chamber below the liquid collecting port; the valve cavity is Processed in conjunction with the valve body; the valve body is a cylinder that can rotate in a closed manner in the valve cavity; the inside of the valve body is a hollow bottle-shaped structure, the top sealing cover is processed into a fixed knob, and a reagent is processed in the center of the knob Opening and closing port: A through square hole is processed on the side wall of the middle part of the valve body. The size of the square hole is consistent with the size of the interface between the sample distribution channel and the valve cavity, and is consistent with the size of the valve cavity and the liquid accumulation port. The liquid-gathering port is a circular frustum-shaped through channel with a large upper part and a smaller lower part, and the liquid-equalizing chamber communicates with it below; the liquid-homogenizing chamber is composed of a cavity and a hemisphere, and the hemisphere is suspended in the liquid-equalizing chamber by a support frame The lower part of the liquid equalizing chamber is directly above the hemisphere of the liquid equalizing chamber. The size of the outlet of the lower part of the liquid accumulating port can be adjusted to ensure that the liquid flowing out of the valve falls on the hemisphere of the liquid equalizing chamber in the form of droplets; The liquid outlet area is composed of a collection pool and a retractable liquid outlet interface; the collection pool is under the liquid equalization chamber, communicated with the liquid equalization chamber, and collects and stores the mixed droplets passing through the hemisphere of the liquid equalization chamber The liquid outlet interface is a telescopic interface, and slide rails are processed on both sides of the liquid outlet interface for connection with the cuvette; the liquid outlet area at the bottom of the chip is also processed with a handle for controlling the telescopic liquid outlet interface ; The bottom of the chip is processed with a sealing bottom cover that seals the bottom surface of the entire chip. 2. A multi-channel microfluidic chip used in conjunction with a cuvette according to claim 1, characterized in that: each of the sample-dividing channels can be combined with a liquid-dispensing port, and continue to be divided into three Sampling channel, that is, one chip can be divided into 9 sampling channels, and the functional components connected to the sampling channel are increased one by one, which can form 9 kinds of mixed solutions and connect 9 cuvettes; the main channel and the dividing channel The sample channel is treated with a hydrophobic surface by plasma treatment; the cavity and the hemisphere in the mixing zone are treated with a hydrophobic surface. 3. A kind of multi-channel microfluidic chip used in conjunction with cuvette according to claim 1, characterized in that: said shunt column is on the center line of the liquid separation port channel; 2 small shunt columns are arranged in rows On both sides of its rear portion; the said diversion island is fusiform, and the tip of the diversion island at its front and the tail point of the island at the tail are all on the center line of the liquid distribution port channel; The opening of the side sampling channel is processed with a concave surface in the middle. 4. A multi-channel microfluidic chip used in conjunction with cuvettes according to claim 1, characterized in that: the size of the outlet of the lower part of the liquid-gathering port can be put into the liquid-gathering port with different diameters. The drip beads in the mouth are adjusted, and the drip beads in each liquid collection port are protected from falling out and replaced by a protective screen.

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