A method for improving digital microfluidic waste disposal

Abstract

The application discloses a method for improving digital micro-fluidic waste liquid treatment, and belongs to the field of micro-fluidic chip waste liquid treatment; in the library reaction process, the existing micro-fluidic chip needs to treat waste liquid 13 times, the operation is complicated, and the test time is greatly increased. The method comprises the following steps: step 1, setting a micro-fluidic chip structure; step 2, treating waste liquid according to a biological library system process; comprising: step 21, first round amplification; step 22, purifying first round amplification products and treating waste liquid; step 23, second round amplification; step 24, purifying second round amplification products and treating waste liquid; step 25, end repair; step 26, purifying end repair products and treating waste liquid; step 27, sequencing adaptor connection; step 28, purifying connection products and treating waste liquid; and step 29, library quantification. The application does not need to repeatedly take out waste liquid in the biological library system process, simplifies the operation steps, and saves the working time.

Description

Technical Field

[0001] This invention relates to the field of microfluidic chip waste liquid treatment technology, and in particular to an improved method for treating digital microfluidic waste liquid. Background Technology

[0002] Digital microfluidics (DMF) is an advanced microdroplet processing technology based on the principle of electrowetting. By applying potential to electrodes, it enables precise control of microliter-sized droplets on an electrode array coated with a hydrophobic layer, including operations such as merging, mixing, dispensing, and separating.

[0003] In recent years, new microfluidic technologies have gradually developed and gained recognition and attention from many scientists. One such technology is Digital Microfluidics (DMF), a novel technique for manipulating microdroplets. Broadly speaking, it belongs to the category of technologies that drive discrete microdroplets based on surface effects. More specifically, it is a full-range droplet manipulation technology that achieves precise control of picoliter or microliter-level discrete droplets on hydrophobic surfaces based on the principle of dielectric wetting. By sequentially applying electrical signals to electrodes, operations such as droplet generation, fusion, mixing, and splitting can be achieved.

[0004] DMF has the following advantages: (1) low sample consumption, fast heat transfer rate, and high parallelism; (2) strong automated control capability and scalability; (3) miniaturization and portability, making it easy to integrate and use with other analytical devices; (4) simple chip design and fabrication, not dependent on micropumps, microvalves, micromixers and other components and complex three-microfluidic channels, and the droplet path can be customized, overcoming the obstacles to the promotion and customization of biochips; (5) the good sealing of digital microfluidic chips effectively reduces the risk of contamination and infection in the detection of infectious samples.

[0005] In microfluidic chip structures, when reagents are injected onto the chip surface through injection holes, the electrodes, when energized, generate an electric field that drives the droplets to move towards the center of the chip. According to the library construction reaction process, waste liquid needs to be removed and treated after each reagent reaction step, requiring a total of 13 waste liquid treatments, with a total waste liquid volume of 118 μl. This significantly increases operation time and wastes raw materials. Summary of the Invention

[0006] Based on the above analysis, the present invention aims to provide an improved method for the treatment of waste liquid in digital microfluidics, in order to solve the problem that in the process of building a reservoir, the existing microfluidic chip requires the waste liquid to be treated 13 times, which is cumbersome and greatly increases the test time.

[0007] The objective of this invention is mainly achieved through the following technical solutions: This invention provides a method for improving digital microfluidic waste liquid treatment, the method comprising the following steps: Step 1: Set up the microfluidic chip structure; the microfluidic chip includes a waste liquid treatment component; the waste liquid treatment component can promptly treat the waste liquid generated during the reaction; Step 2: According to the biobank construction system process, treat the wastewater using wastewater treatment components; including the following processes: Step 21, First round of amplification: Inject 5 μl of 2x PCR, Mix, λ primer and sample nucleic acid respectively, and perform the first round of amplification according to the reaction conditions; Step 22: Purify the first-round amplification product and treat the waste liquid using the waste liquid treatment unit; Step 23, Second round of amplification: Add 5 μl of primer to the purified product from the first round of amplification and then proceed with the reaction; Step 24: Purify the second-round amplification product and treat the waste liquid using the waste liquid treatment unit; Step 25, End Repair; Inject 5 μl of a mixture of enzyme-free water, repair buffer, end repair enzyme, and DNA repair enzyme, and complete the end repair reaction according to the system requirements. After magnetic separation, discard the magnetic beads. Step 26: Purify the end-repair products and treat the waste liquid using the waste liquid treatment unit; Step 27: Sequencing adapter ligation; Step 28: Connect the purified product and treat the waste liquid using the waste liquid treatment unit; Step 29, Library Quantification: Perform instrumental testing on the purified ligation product.

[0008] Furthermore, in step 1, the microfluidic chip also includes a chip body, and the waste liquid treatment component is disposed on the chip body; The chip body includes a driving backplane, a top glass, and a host computer. The driving backplane and the top glass are horizontally arranged and parallel to each other. The top glass is located directly above the driving backplane. The area between the top glass and the driving backplane is the chip functional area. The driving backplane is provided with driving electrodes, which are connected to the host computer for control. The host computer can control the driving electrodes to drive the test droplets located in the chip functional area and thus move the test droplets.

[0009] Furthermore, in step 1, the waste liquid treatment component includes a chip shell; the chip shell has a hollow structure and an open end, the open end of the chip shell is located on the upper surface of the top glass; a superabsorbent polymer material is provided inside the chip shell, and the area where the superabsorbent polymer material is located constitutes a waste liquid storage pool; the waste liquid storage pool is connected to the functional area of ​​the chip.

[0010] Furthermore, in step 1, the chip casing and the chip body are designed as a single unit.

[0011] Furthermore, in step 1, a first through hole is provided on the top glass and a second through hole is provided on the bottom of the chip casing. The first through hole and the second through hole are positioned correspondingly and connected to each other, and together they form a waste liquid movement channel. Capillary adsorption material is provided in the waste liquid movement channel.

[0012] Further, in step 22, the purification of the first-round amplification product and the treatment of waste liquid using the waste liquid treatment unit include the following processes: Step 221: Inject 5 μl of DNA purification magnetic beads to react with the first round of amplification products. After the reaction is complete, magnetically separate until the solution is clear, then discard the supernatant. The volume of the waste liquid is 10 μl. Step 222: Use the host computer to control the drive electrode to move the waste liquid. Use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component. Use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the first waste liquid treatment.

[0013] Furthermore, in step 22, the purification of the first-round amplification product and the treatment of waste liquid using the waste liquid treatment unit also include the following processes: Step 223: Inject 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 224: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, and use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the second waste liquid treatment.

[0014] Furthermore, in step 22, the purification of the first-round amplification product and the treatment of waste liquid using the waste liquid treatment unit also include the following processes: Step 225: Inject another 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 226: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, and use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the third waste liquid treatment.

[0015] Further, in step 24, the purification of the second-round amplification product and the treatment of waste liquid using the waste liquid treatment unit include the following steps: Step 241: Inject 5 μl of DNA purification magnetic beads and react with the second round of amplification products. After the reaction is complete, separate them magnetically. After the solution is clear, discard the supernatant. The volume of waste liquid is 10 μl. Step 242: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid, and complete the fourth waste liquid treatment. Step 243: Inject 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 244: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid, and complete the fifth waste liquid treatment.

[0016] Furthermore, in step 24, the purification of the second-round amplification product and the treatment of waste liquid using the waste liquid treatment unit also include the following steps: Step 245: Inject another 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 246: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, and use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the sixth waste liquid treatment.

[0017] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: (1) By setting a waste liquid treatment component on the chip body, the present invention drives the waste liquid to the waste liquid outlet according to the biological library construction system process and relies on digital microfluidic technology to remove the waste liquid using the waste liquid treatment component, thereby avoiding repeated treatment of waste liquid in the biological library construction system process and greatly saving operation time.

[0018] (2) The present invention sets a chip shell on the chip body and sets a superabsorbent polymer material inside the chip shell. The superabsorbent polymer material can adsorb hundreds of times its own weight of water. The waste liquid can be transported to the waste liquid treatment area in time through the capillary adsorption material and thus be absorbed cleanly in time.

[0019] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0020] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0021] Figure 1 is a schematic diagram of the microfluidic chip of the present invention.

[0022] Figure label: 1-Drive backplate; 2-Drive electrode; 3-Top glass; 4-Chip shell; 5-High molecular weight absorbent material; 6-Waste liquid storage tank; 7-Waste liquid movement channel; 8-Capillary adsorption material; 9-Waste liquid. Detailed Implementation

[0023] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0024] This invention provides a method for improving digital microfluidic waste liquid treatment, comprising the following steps: Step 1: Set up the microfluidic chip structure; the microfluidic chip includes a waste liquid treatment component; the waste liquid treatment component can promptly treat the waste liquid generated during the reaction. In step 1 above, as Figure 1 As shown, the microfluidic chip also includes a chip body, and a waste liquid treatment component is disposed on the chip body. The chip body includes a driving backplate 1, a top glass 3, and a host computer. The driving backplate 1 and the top glass 3 are both horizontally arranged and parallel to each other. The top glass 3 is located directly above the driving backplate 1. The area of ​​the top glass 3 between the driving backplate 1 constitutes the chip functional area of ​​the microfluidic chip. The driving backplate 1 is provided with a driving electrode 2, which is connected to the host computer for control. The host computer can control the driving electrode 2 to drive the test droplet located in the chip functional area and thus move the droplet.

[0025] It should be noted that in step 1 above, the driving electrode 2 is fabricated on the driving back plate 1, the driving back plate 1 is the carrier of the driving electrode 2, and the top glass 3 is the parallel electrode. In this way, during the power-on process, the top glass 3 and the driving electrode 2 can form a parallel electric field. The power-on and power-off of the driving electrode 2 can be controlled by the host computer software to realize the control of the electric field and complete the movement of the droplet under the action of the electric field.

[0026] In step 1 above, the waste liquid treatment component includes a chip shell 4, which is a hollow structure with an open end. The open end of the chip shell 4 is located on the upper surface of the top glass 3. A super absorbent polymer 5 is provided inside the chip shell 4. The area where the super absorbent polymer 5 is located constitutes a waste liquid storage pool 6. The waste liquid storage pool 6 is connected to the functional area of ​​the chip.

[0027] In step 1 above, the top glass 3 is provided with a first through hole, and the bottom of the chip shell 4 is provided with a second through hole. The first through hole and the second through hole are in corresponding positions and connected to each other. Together they form a waste liquid movement channel 7, that is, the waste liquid movement channel 7 is connected to the chip functional area and the waste liquid storage pool 6. A capillary adsorption material 8 is provided along the length of the waste liquid movement channel 7.

[0028] It should be noted that the chip casing 4 is designed as an integral part of the chip body. After each test, both the chip body and the chip casing 4 are disposed of as disposable items to avoid the influence of waste liquid 9 on the reagent reaction during the test.

[0029] It should be noted that the aforementioned superabsorbent polymer 5 is fixed on the chip casing 4 to prevent the superabsorbent polymer 5 from moving inside the chip casing 4 after absorbing water; in addition, the capillary adsorption material 8 is fixed inside the waste liquid movement channel 7 to prevent the position of the capillary adsorption material 8 from changing inside the waste liquid movement channel 7.

[0030] In step 1 above, when waste liquid 9 is generated in the chip functional area, the host computer software controls the drive electrode 2 to move the waste liquid to the position of the waste liquid movement channel 7 in the chip functional area. Utilizing the capillary action of the capillary adsorption material 8 in the waste liquid movement channel 7, the waste liquid 9 in the chip functional area is gradually absorbed cleanly. After passing through the capillary adsorption material 8, it is transported to the polymer absorbent material in the waste liquid 9 area. Based on the characteristics of the polymer absorbent material, it can absorb hundreds of times its own weight in water, and the waste liquid 9 will be absorbed cleanly very quickly.

[0031] It should be emphasized that the waste liquid treatment component of the present invention also includes a fixing frame, which is disposed inside the chip shell 4. The fixing frame includes multiple layers of filamentous mesh, and the space between adjacent filamentous meshes is filled with superabsorbent polymer material 5. The superabsorbent polymer material 5 is fixed by the multiple layers of filamentous mesh, which ensures that the superabsorbent polymer material 5 has good water absorption and air permeability, and avoids it from absorbing a large amount of water and gathering together, which would affect the water absorption effect.

[0032] In step 1 above, the aforementioned superabsorbent polymer 5 is a superabsorbent polymer (SAP), also known as a super absorbent. SAP can absorb hundreds of times its own weight in water because: First, SAP contains strong hydrophilic groups (such as hydroxyl and carboxyl groups). These polymer molecules can form hydrogen bonds with water molecules, thus exhibiting a high affinity for water and rapidly absorbing and swelling upon contact. Second, SAP has a cross-linked structure, preventing it from dissolving into a solution when interacting with water. Third, SAP contains a high concentration of ionic groups. The presence of numerous ionic groups ensures a high ion concentration within the system, creating a high osmotic pressure pointing inwards. Under this osmotic pressure, water in the environment tends to diffuse into the system, thus enhancing its absorbency. Finally, SAP has a high molecular weight. Increased molecular weight increases mechanical strength after water absorption, further enhancing its absorbency.

[0033] It should be noted that the superabsorbent polymer used in this invention is an existing material, which includes sodium polyacrylate (chemical formula [-CH2-CH(COONa)-]). n Among them, sodium polyacrylate SAP has a molecular weight <10000, and the water absorption mechanism of sodium polyacrylate SAP is as follows: -CH2=CH-COOH +NaOH→ -CH2=CH-COONa+H2O (1) n(-CH2=CH-COONa)→[-CH2-CH(COONa)]n(2) As can be seen from equations (1) and (2), sodium polyacrylate can bridge into a network structure, with a higher internal ion concentration than the external one, resulting in osmotic pressure.

[0034] Step 2: According to the biobank construction system process, treat waste liquid 9. The biobank construction system process is shown in Table 1 below; specifically, it includes the following sub-steps: Step 21, First round of amplification; The specific process is as follows: inject 5 μl of 2x PCR, Mix, λ primer and sample nucleic acid respectively, and carry out the first round of amplification according to the reaction conditions; Step 22: Purify the first-round amplification products and treat the waste liquid (9); specifically including the following sub-steps: Step 221: Inject 5 μl of DNA purification magnetic beads to react with the first round of amplification products. After the reaction is complete, magnetically separate until the solution is clear, then discard the supernatant. The volume of waste liquid 9 is 10 μl. Step 222: Use the host computer to control the drive electrode 2 to move the waste liquid 9, use the capillary adsorption material 8 to transfer 10μl of waste liquid 9 to the waste liquid treatment component, and use the polymer water-absorbing material 5 to adsorb the 10μl of waste liquid 9 to complete the first waste liquid treatment. Specifically, the host computer controls the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, the 10μl waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, thus completing the first waste liquid treatment.

[0035] Step 223: Inject 10 μl of SWB (or SJ-1) solution, mix thoroughly, complete magnetic separation, and discard the supernatant after the solution becomes clear. The volume of waste liquid is 10 μl. Step 224: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, the 10μl waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, thus completing the second waste liquid treatment. Step 225: Inject another 10 μl of SWB (or SJ-1) solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of waste liquid 9 is 10 μl; that is, the purification of the first round of amplification products produces 30 μl of waste liquid 9. Step 226: Using the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening, through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed cleanly. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, thus completing the third waste liquid treatment.

[0036] Step 23, Second round of amplification; The specific process is as follows: 5 μl of primer is added to the purified product of the first round of amplification and then the reaction is carried out.

[0037] Step 24: Purify the second-round amplification products and treat the waste liquid (9), specifically including the following sub-steps: Step 241: Inject 5 μl of DNA purification magnetic beads and react with the second round of amplification products. After the reaction is complete, separate them magnetically. After the solution is clear, discard the supernatant. The volume of waste liquid 9 is 10 μl. Step 242: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the superabsorbent polymer 5 through the capillary adsorption material 8 and is completely adsorbed by the superabsorbent polymer 5, thus completing the fourth waste liquid treatment. Step 243: Inject 10 μl of SWB (or SJ-1) solution, mix thoroughly, complete magnetic separation, and discard the supernatant after the solution becomes clear. The volume of waste liquid 9 is 10 μl. Step 244: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, completing the fifth waste liquid treatment. Step 245: Inject another 10 μl of SWB (or SJ-1) solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of waste liquid 9 is 10 μl. That is, the second round of amplification product purification produces a total of 30 μl of waste liquid 9. Step 246: Using the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening, through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, completing the sixth waste liquid treatment.

[0038] Step 25, End Repair; The specific process is as follows: inject 5 μl of a mixture of enzyme-free water, repair buffer, end repair enzyme, and DNA repair enzyme, complete the end repair reaction according to the system requirements, and discard the magnetic beads after magnetic separation.

[0039] Step 26: Purify the end-repair products and treat the waste liquid; specifically including the following sub-steps: Step 261: Inject 5 μl of DNA purification magnetic beads and react with the end repair product. After the reaction is complete, separate them magnetically. After the solution is clear, discard the supernatant. The volume of waste liquid 9 is 10 μl. Step 262: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, completing the seventh waste liquid treatment. Step 263: Inject 10 μl of SWB (or SJ-1) solution, mix thoroughly, complete magnetic separation, and discard the supernatant after the solution becomes clear. The volume of waste liquid 9 is 10 μl. Step 264: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the superabsorbent polymer 5 through the capillary adsorption material 8 and is completely adsorbed by the superabsorbent polymer 5, completing the eighth waste liquid treatment. Step 265: Inject another 10 μl of SWB (or SJ-1) solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of waste liquid 9 is 10 μl. Step 266: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the superabsorbent polymer 5 through the capillary adsorption material 8 and is completely adsorbed by the superabsorbent polymer 5, completing the ninth waste liquid treatment. Step 267: Inject 3 μl of NF water, mix thoroughly, and then complete the magnetic separation. After magnetic separation, discard the magnetic beads and 1 μl of the purified sample containing the end-repair product. That is, the purification reaction of the end-repair product generates 31 μl of waste liquid 9. Step 268: Using the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening, through the capillary action of the capillary adsorption material 8, 1μl of waste liquid 9 is gradually adsorbed cleanly. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, completing the tenth waste liquid treatment.

[0040] Step 27: Sequencing adapter ligation; The specific process is as follows: mix 2 μl of the purified end-repair product and 1 μl of the sequencing ligation adapter thoroughly, then add 2 μl of the ligation reaction solution to make a total of 5 μl of reagents and mix evenly, then run the reaction program.

[0041] Step 28: Purify the ligation product and treat the waste liquid; specifically including the following sub-steps: Step 281: Inject 2 μl of DNA purification magnetic beads and mix with the purified sample of end repair product. After the reaction is complete, perform magnetic separation. After the solution is clear, discard the supernatant. The volume of waste liquid is 7 μl. Step 282: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, the 7μl waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the polymer water-absorbing material 5 through the capillary adsorption material 8 and is completely adsorbed by the polymer water-absorbing material 5, completing the eleventh waste liquid treatment. Step 283: Inject 10 μl of SWB (or SJ-1) solution, mix thoroughly, complete magnetic separation, and discard the supernatant after the solution becomes clear. The volume of waste liquid 9 is 10 μl. Step 284: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the superabsorbent polymer 5 through the capillary adsorption material 8 and is completely adsorbed by the superabsorbent polymer 5, thus completing the twelfth waste liquid treatment. Step 285: Inject another 10 μl of SWB (or SJ-1) solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of waste liquid is 10 μl. Step 286: Use the host computer to control the drive electrode 2 to move the waste liquid 9 to the waste liquid channel opening. Through the capillary action of the capillary adsorption material 8, 10μl of waste liquid 9 is gradually adsorbed clean. The waste liquid 9 is transferred to the superabsorbent polymer 5 through the capillary adsorption material 8 and is completely adsorbed by the superabsorbent polymer 5, completing the thirteenth waste liquid treatment. Step 287: Inject 10 μl of AEB to resuspend, mix well and let stand for 5 min, aspirate the supernatant to obtain the final product, and discard the magnetic beads; a total of 27 μl of waste liquid was generated during the purification of the ligation product. Step 29: Quantitative analysis of the library.

[0042] The specific process is as follows: the purified sample of the ligation product was tested on the instrument, and the library construction system generated a total of 118 μl of waste liquid in 13 separate tests.

[0043] Table 1. Schematic diagram of the biobank construction system

[0044] Compared with the prior art, on the one hand, the method for improving the treatment of digital microfluidic waste liquid 9 provided by the present invention targets the waste liquid 9 generated during the construction process. The present invention utilizes the advantages of digital microfluidics to move the waste liquid after reaction to the waste liquid storage tank 6. This method eliminates the need to aspirate the waste liquid 9, reduces the use of pipette tips, thereby reducing working time and lowering experimental costs, and ultimately shortening the experimental cycle.

[0045] On the other hand, since the superabsorbent polymer 5 is embedded in the chip casing 4, it is treated as a disposable item after each test, thus avoiding the influence of waste liquid 9 on the reagent reaction during the test.

[0046] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for improving digital microfluidic waste liquid treatment, characterized in that, Includes the following steps: Step 1: Set up the microfluidic chip structure; the microfluidic chip includes a waste liquid treatment component; the waste liquid treatment component can promptly treat the waste liquid generated by the reaction; Step 2: According to the biobank construction system process, treat the wastewater using wastewater treatment components; including the following processes: Step 21, First round of amplification: Inject 5 μl of 2x PCR, Mix, λ primer and sample nucleic acid respectively, and perform the first round of amplification according to the reaction conditions; Step 22: Purify the first-round amplification product and treat the waste liquid using the waste liquid treatment component; Step 23, Second round of amplification: Add 5 μl of primer to the purified product from the first round of amplification and then proceed with the reaction; Step 24: Purify the second round of amplification products and treat the waste liquid using the waste liquid treatment component; Step 25, End Repair; Inject 5 μl of a mixture of enzyme-free water, repair buffer, end repair enzyme, and DNA repair enzyme, and complete the end repair reaction according to the system requirements. After magnetic separation, discard the magnetic beads. Step 26: Purify the end-repair products and treat the waste liquid using the waste liquid treatment component; Step 27: Sequencing adapter ligation; Step 28: Connect the product purification and treat the waste liquid using the waste liquid treatment component; Step 29, Library Quantification: Perform instrumental testing on the purified ligation product. The microfluidic chip also includes a chip body, and the waste liquid treatment component is disposed on the chip body; The chip body includes a driving backplate, a top glass, and a host computer; the driving backplate and the top glass are horizontally arranged and parallel to each other, the top glass is located directly above the driving backplate, and the area between the top glass and the driving backplate is the chip functional area; the driving backplate is provided with driving electrodes, the driving electrodes are controlled and connected to the host computer, and the host computer can control the driving electrodes to drive the test droplet located in the chip functional area and thus move the test droplet; The waste liquid treatment component includes a chip shell; the chip shell has a hollow structure and an open end, the open end of the chip shell being located on the upper surface of the top glass; a superabsorbent polymer material is disposed inside the chip shell, the area where the superabsorbent polymer material is located constitutes a waste liquid storage tank; the waste liquid storage tank is connected to the functional area of ​​the chip; The top glass is provided with a first through hole, and the bottom of the chip shell is provided with a second through hole. The first through hole and the second through hole are in corresponding positions and connected to each other. Together they form a waste liquid movement channel, and the waste liquid movement channel is provided with capillary adsorption material.

2. The method for improving digital microfluidic waste liquid treatment according to claim 1, characterized in that, In step 1, the chip casing is designed as an integral part of the chip body.

3. The method for improving digital microfluidic waste liquid treatment according to claim 1 or 2, characterized in that, In step 22, the purification of the first-round amplification product and the treatment of waste liquid using the waste liquid treatment component include the following processes: Step 221: Inject 5 μl of DNA purification magnetic beads to react with the first round of amplification products. After the reaction is complete, magnetically separate until the solution is clear, then discard the supernatant. The volume of the waste liquid is 10 μl. Step 222: Use the host computer to control the drive electrode to move the waste liquid. Use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component. Use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the first waste liquid treatment.

4. The method for improving digital microfluidic waste liquid treatment according to claim 3, characterized in that, In step 22, the purification of the first-round amplification product and the waste liquid treatment using the waste liquid treatment component also... The process includes the following: Step 223: Inject 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 224: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, and use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the second waste liquid treatment.

5. The method for improving digital microfluidic waste liquid treatment according to claim 4, characterized in that, In step 22, the purification of the first-round amplification product and the waste liquid treatment using the waste liquid treatment component also... The process includes the following: Step 225: Inject another 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 226: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, and use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the third waste liquid treatment.

6. The method for improving digital microfluidic waste liquid treatment according to claim 5, characterized in that, In step 24, the purification of the second-round amplification product and the treatment of waste liquid using the waste liquid treatment component include the following steps: Step 241: Inject 5 μl of DNA purification magnetic beads and react with the second round of amplification products. After the reaction is complete, separate them magnetically. After the solution is clear, discard the supernatant. The volume of waste liquid is 10 μl. Step 242: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid, and complete the fourth waste liquid treatment. Step 243: Inject 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 244: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid, and complete the fifth waste liquid treatment.

7. The method for improving digital microfluidic waste liquid treatment according to claim 6, characterized in that, In step 24, the purification of the second-round amplification product and the treatment of waste liquid using the waste liquid treatment component further include the following steps: Step 245: Inject another 10 μl of SWB solution, mix thoroughly, and complete magnetic separation. After the solution becomes clear, discard the supernatant. The volume of the waste liquid is 10 μl. Step 246: Use the host computer to control the drive electrode to move the waste liquid, use capillary adsorption material to transfer 10μl of waste liquid to the waste liquid treatment component, and use polymer water-absorbing material to adsorb and treat the 10μl of waste liquid to complete the sixth waste liquid treatment.

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