Fully enclosed nucleic acid rapid test strip microfluidic chip and its portable system

Abstract

The present invention discloses a fully enclosed nucleic acid rapid test strip detection microfluidic chip and its portable system. In the upper layer of the fully enclosed nucleic acid rapid test strip detection microfluidic chip, the amplification reaction reservoir chamber is connected to the upper section hole of the sample and lysis solution loading hole through a first microchannel, and the amplification reaction reservoir chamber is connected to the amplification solution loading hole. An amplification solution loading hole plug is correspondingly arranged inside the amplification solution loading hole; in the middle layer, the middle section hole of the sample and lysis solution loading hole is connected to the upper chamber of the storage chamber through a second microchannel, and the upper section hole of the sample and lysis solution loading hole is connected to the middle section hole of the sample and lysis solution loading hole to form the sample and lysis solution loading hole. A reaction chamber loading hole plug is correspondingly arranged inside the sample and lysis solution loading hole; in the lower layer, the reaction chamber is connected to the lower chamber of the storage chamber through a third microchannel, and the detection chamber is connected to the lower chamber of the storage chamber and a nucleic acid rapid test strip is arranged inside. Among them, the lower chamber of the storage chamber is connected to the upper chamber of the storage chamber to form the storage chamber.

Description

Technical Field

[0001] The present invention relates to the technical field of microfluidic chips, and particularly to a fully enclosed nucleic acid rapid test strip detection microfluidic chip and its portable system. Background Art

[0002] With the rapid development of molecular biology technology, molecular diagnosis technology has developed rapidly and has been widely used in medical tests and clinical medical diagnosis. Molecular diagnosis technology refers to the technology that uses molecular biology methods, targets biomolecules, and detects changes in the structure or expression level of endogenous genetic materials (deoxyribonucleic acid DNA or ribonucleic acid RNA) or exogenous biomolecules and systems in organisms to make a diagnosis. Its main applications include disease-specific diagnosis, early screening and diagnosis of diseases, identification and typing of pathogenic organisms causing infections, tracking the disease development process, etc., and it has very important scientific research value and practical application prospects. Molecular diagnosis of viruses plays an important role in both molecular diagnosis and actual medical tests and clinical medical diagnosis. There are a wide variety of virus species that can be detected by virus molecular diagnosis. Just for respiratory viruses, there are influenza A virus, influenza B virus, adenovirus, respiratory syncytial virus, parainfluenza virus, human rhinovirus, human metapneumovirus, avian influenza virus, SARS-Cov virus, COVID-19 virus, human bocavirus, etc.

[0003] Rapid molecular diagnosis or point-of-care testing (POCT) of viruses is one of the important research contents and important development trends of virus molecular diagnosis. For example, for the rapid detection of COVID-19 virus, miniaturized or portable detection instruments based on nucleic acid detection, miniaturized or portable detection instruments based on antigen-antibody detection, immunochromatographic test strips based on nucleic acid detection, immunochromatographic test strips based on antigen-antibody detection, etc. have been developed. Since the main requirements for rapid molecular diagnosis of viruses are: (1) high biosafety; (2) accurate and reliable detection results; (3) short detection time; (4) low detection cost; (5) convenient detection operation. Among the above detection methods, the immunochromatographic test strip based on nucleic acid detection has significant advantages over other methods in terms of reliable detection results and low detection cost, so it has received more and more attention from relevant researchers and enterprises.

[0004] However, currently, for the biosafety of nucleic acid detection-based immunochromatographic test strips and systems, mainly a method of setting filter membranes at the fluid inlets and outlets of the detection system is adopted to prevent high-concentration nucleic acids from leaking into the environment, or the problem of high-concentration nucleic acid leakage is not fully considered. The method of setting filter membranes or similar methods cannot completely solve the problem of the remaining risk of high-concentration nucleic acid leakage during the detection process and when dealing with waste after the detection, because there is essentially material exchange with the external environment at the fluid inlets and outlets of the detection system. If high-concentration nucleic acids leak, only the leakage amount can be reduced to a certain extent, but the leakage risk cannot be completely solved. And once high-concentration pathogenic viruses leak, serious consequences may occur.

[0005] Currently, for the accuracy of the detection results and the convenience of the detection operation of nucleic acid detection-based immunochromatographic test strips and systems, the nucleic acid amplification function, and even the nucleic acid extraction function, are often integrated into a miniaturized or portable system. For an integrated system, the more functions it integrates, the more reasonable balance is needed in the pursuit of the performance of each function. For example, when integrating functions such as lysis function, nucleic acid purification function, nucleic acid amplification function, and nucleic acid detection function into a miniaturized or portable system, when the number of functions increases but the functional structures are not deeply integrated, the accuracy of the detection results is often greatly reduced. When fully considering the biosafety requirements of nucleic acid detection-based immunochromatographic test strips and systems, the processes involving high-concentration nucleic acids are mainly nucleic acid amplification and nucleic acid detection. Therefore, sacrificing a part of the convenience of the detection operation or sacrificing the nucleic acid purification function can, to a certain extent, exchange for an opportunity to improve the accuracy of the detection results. To improve the accuracy of the detection results, it is also necessary to deeply integrate the lysis function, nucleic acid amplification function, and nucleic acid detection function in the structural design. A common integration method is to integrate the lysis function and the nucleic acid amplification function in the same chamber. To ensure the activity of the biological reagents used for amplification, the temperature often cannot be heated to a temperature suitable for lysis, which will ultimately result in a loss of the nucleic acid detection effect.

[0006] At present, the nucleic acid detection-based immunochromatographic test strip and system integrating the functions of lysis, nucleic acid amplification, and nucleic acid detection are mainly designed in an integrated manner. Its temperature control component is integrated with the flow control component and the test strip in one system. The pursuit of miniaturization and low cost often leads to certain losses in the functionality and accuracy of the temperature control function. At the same time, in the integrated design, the heat and temperature control components need to be discarded together with the test strip, which is not economical for users and is not conducive to the conservation and effective utilization of metal minerals, as well as environmental protection. To reduce the overall and long-term usage costs of users, a solution where the temperature control component, the flow control component, and the test strip are each a subsystem, and the temperature control component can be reused without being discarded, can not only significantly improve the performance of the temperature control function, but also is of great significance for reducing the overall usage cost, effectively conserving and utilizing metal minerals, and environmental protection.

[0007] In summary, the problems in the prior art are as follows: 1. During the rapid nucleic acid detection process and when dealing with waste after the rapid nucleic acid detection, there is a risk of leakage of high-concentration nucleic acid. After the leakage of high-concentration pathogenic viruses, serious consequences will occur; 2. When integrating functions such as lysis function, nucleic acid amplification function, and nucleic acid detection function, the lack of in-depth integration leads to the need to improve the effect and performance of rapid nucleic acid detection; 3. The overall and long-term usage costs of users are high, and it cannot flexibly adapt to changes in the number of people or samples for home rapid nucleic acid detection.

[0008] In the patent with the publication number CN 113512490A, a self-driven microfluidic detection device is proposed. This device integrates the functions of lysis, isothermal nucleic acid amplification, and nucleic acid test strip detection, and can perform rapid virus detection to a certain extent. However, the device integrates the lysis function and the isothermal nucleic acid amplification function in one chamber without time or space isolation. To ensure the effectiveness of the lysis and isothermal nucleic acid amplification functions and the activity of biological reagents, a relatively high lysis temperature cannot be used. When the lysis solution and the amplification solution are in the same chamber simultaneously, it is difficult to achieve the optimal biochemical reaction environment for each, which will affect the detection effect. During the use of this device, two sample additions are required. Especially after the isothermal amplification is completed, a dilution liquid needs to be added to raise the liquid level in the storage pool so that the reacted liquid can contact the test strip. However, after the isothermal amplification, a high concentration of nucleic acid already exists in the entire device. To prevent the leakage of the high-concentration nucleic acid, a filter membrane solution is adopted, but this solution cannot eliminate the leakage risk. The device integrates the temperature control component, the flow control component, and the test strip in one system and discards them together after use, which is not economical for users, is not conducive to the conservation and effective utilization of metal minerals, and is also not environmentally friendly. This device is a self-driven microfluidic detection device with a capillary force driving method. The advantage of this driving method is that only a capillary structure needs to exist, but the disadvantage is that the fluid velocity driven by capillary force is very small, which is not conducive to the rapid detection of nucleic acids and does not meet the requirement of rapid detection. Summary of the Invention

[0009] To solve the problems existing in the above-mentioned prior art, the present invention provides a fully enclosed nucleic acid rapid test strip detection microfluidic chip and its portable system, which can effectively solve the above problems and perform rapid and effective nucleic acid detection.

[0010] To achieve the above technical objectives, the present invention provides the following technical solutions:

[0011] A fully enclosed nucleic acid rapid test strip detection microfluidic chip, comprising:

[0012] The upper layer, middle layer, and lower layer sealed into a fully enclosed nucleic acid rapid test strip detection microfluidic chip;

[0013] Among them, the upper layer is provided with an amplification solution sampling hole, an amplification reaction storage chamber, a first microchannel, and an upper section hole of the lysis solution sampling hole. The amplification reaction storage chamber is connected to the sample and the upper section hole of the lysis solution sampling hole through the first microchannel. The amplification reaction storage chamber is connected to the amplification solution sampling hole, and an amplification solution sampling hole plug is correspondingly arranged inside the amplification solution sampling hole;

[0014] The middle layer is provided with a middle-section sample and lysis solution loading holes, a second microchannel, and an upper chamber of the liquid storage chamber; the middle-section holes of the sample and lysis solution loading holes are communicated with the upper chamber of the liquid storage chamber through the second microchannel, and the upper-section holes of the sample and lysis solution loading holes are communicated with the middle-section holes of the sample and lysis solution loading holes to form the sample and lysis solution loading holes. A reaction chamber loading hole plug is correspondingly arranged in the sample and lysis solution loading holes.

[0015] The lower layer is provided with a reaction chamber, a third microchannel, a lower chamber of the liquid storage chamber, and a detection chamber. The reaction chamber is communicated with the lower chamber of the liquid storage chamber through the third microchannel. The detection chamber is communicated with the lower chamber of the liquid storage chamber and is internally provided with a nucleic acid rapid detection test strip. The lower chamber of the liquid storage chamber is communicated with the upper chamber of the liquid storage chamber to form the liquid storage chamber.

[0016] Optionally, the amplification solution loading hole plug and the reaction chamber loading hole plug are made of rubber or silica gel materials.

[0017] To better achieve the above technical objectives, the present invention also provides a portable system for a fully enclosed nucleic acid rapid test strip detection microfluidic chip, including: a portable multi-channel high-precision temperature control system and a fully enclosed nucleic acid rapid test strip detection microfluidic chip. The portable multi-channel high-precision temperature control system includes: a temperature adjustment execution device, a sensing module, a microcontroller, a touch screen, a step-down module, a power supply module, and a power amplifier circuit.

[0018] The power supply module is respectively connected to the microcontroller and the touch screen through the step-down module to supply power to the microcontroller and the touch screen respectively; the power supply module is connected to the power amplifier circuit; the sensing module, the microcontroller, the power amplifier circuit, and the temperature adjustment device are sequentially connected; the temperature adjustment device is in contact with the metal block to control the temperature of the metal block, and the sensing module is correspondingly arranged with the metal block; the microcontroller is connected to the touch screen; the microcontroller is used to control the temperature adjustment device through the power amplifier circuit according to the temperature data obtained by the sensing module, and transmit the temperature data to the touch screen for storage and display.

[0019] The temperature adjustment execution device is in contact with a plurality of fully enclosed nucleic acid rapid test strip detection microfluidic chips to achieve portable temperature control of the fully enclosed nucleic acid rapid test strip detection microfluidic chips.

[0020] Optionally, the temperature adjustment execution device includes a multi-channel temperature adjustment device, a metal block, heat insulation materials between the multi-channel temperature adjustment execution devices, and a support structure; the metal block is made of copper or aluminum materials.

[0021] Optionally, the sensing module includes a temperature sensor and an ADC module, and the temperature sensor is fixed near the surface inside the metal block to obtain the temperature data of the metal block.

[0022] Optionally, the heat insulation material between the multiple temperature adjustment actuators in the temperature adjustment actuator is a lightweight porous heat insulation material or a fibrous heat insulation material.

[0023] Optionally, the material of the support structure in the temperature adjustment actuator is a high-temperature resistant and flame-retardant material.

[0024] Optionally, the support structure in the temperature adjustment actuator has a structure for positioning and clamping the fully enclosed nucleic acid rapid test strip detection microfluidic chip.

[0025] Optionally, the power amplifier circuit includes a heating power amplifier circuit, a refrigeration power amplifier circuit, and a heat dissipation fan power amplifier circuit.

[0026] Optionally, the temperature adjustment device includes a heating device, a refrigeration device, and a heat dissipation fan. The heating device uses a PI film heater, and the refrigeration device uses a high-temperature resistant semiconductor refrigeration chip. The heating device and the refrigeration device are attached and in contact with the metal block.

[0027] Optionally, the power supply module includes a DC switching power supply and a rechargeable battery, where the DC switching power supply is connected to the mains.

[0028] Optionally, the buck module uses a DC-DC buck module.

[0029] The present invention has the following technical effects:

[0030] 1. By adopting a fully enclosed structure design to achieve full closure during one-time sample addition, it will effectively solve the problem of high-concentration nucleic acid leakage risk during the nucleic acid rapid detection process and when dealing with waste after the nucleic acid rapid detection.

[0031] 2. Integrating the lysis function, nucleic acid amplification function, and nucleic acid detection function, and separating the lysis function and nucleic acid amplification function in time and space, the temperature and time of the lysis process and amplification process can be precisely controlled. While effectively ensuring the activity of biological reagents, the optimal lysis temperature can be guaranteed; the biochemical reaction environments of the lysis process and amplification process can also reach their respective optima, which will improve the effect and performance of nucleic acid rapid detection.

[0032] 3. Adopting the scheme that the temperature control component, the flow control component, and the test strip are each a subsystem will reduce the overall usage and long-term usage costs of users, and can flexibly adapt to changes in the number of people or samples for home nucleic acid rapid detection. At the same time, the functionality and accuracy of the temperature control component are also easy to be greatly improved. Description of the Drawings

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0034] Figure 1 Schematic diagram of the fully enclosed nucleic acid rapid test strip detection microfluidics and its portable system provided by the embodiment of the present invention;

[0035] Figure 2 Schematic diagram of the overall structure of the fully enclosed nucleic acid rapid test strip detection microfluidic chip provided by the embodiment of the present invention;

[0036] Figure 3 Cross-sectional view of the overall structure of the fully enclosed nucleic acid rapid test strip detection microfluidic chip provided by the embodiment of the present invention;

[0037] Figure 4 Schematic diagram of the upper layer structure of the fully enclosed nucleic acid rapid test strip detection microfluidic chip provided by the embodiment of the present invention;

[0038] Figure 5 Schematic diagram of the middle layer structure of the fully enclosed nucleic acid rapid test strip detection microfluidic chip provided by the embodiment of the present invention;

[0039] Figure 6 Schematic diagram of the lower layer structure of the fully enclosed nucleic acid rapid test strip detection microfluidic chip provided by the embodiment of the present invention;

[0040] Figure 7 Schematic diagram of the structure of the portable multi-channel high-precision temperature control system provided by the embodiment of the present invention;

[0041] Figure 8 Schematic diagram of the temperature curve provided by the embodiment of the present invention;

[0042] Figure 9 Schematic diagram of the working principle provided by the embodiment of the present invention;

[0043] Figure 10 Schematic diagram of the fluid flow situation provided by the embodiment of the present invention;

[0044] Figure 11 Schematic diagram of the hydrodynamic analysis of the concave liquid surface provided by the embodiment of the present invention;

[0045] Figure 12 Schematic diagram of the hydrodynamic analysis of the convex liquid surface provided by the embodiment of the present invention;

[0046] Description of the reference numerals in the drawings: 1 - Portable multi-channel high-precision temperature control system, 2 - Fully enclosed nucleic acid rapid test strip detection microfluidic chip, 11 - Temperature adjustment execution device, 21 - Upper layer of the fully enclosed nucleic acid rapid test strip detection microfluidic chip, 22 - Middle layer of the fully enclosed nucleic acid rapid test strip detection microfluidic chip, 23 - Lower layer of the fully enclosed nucleic acid rapid test strip detection microfluidic chip, 24 - Nucleic acid rapid test strip, 211 - Amplification reaction liquid storage chamber, 231 - Reaction chamber, 25 - Amplification liquid sampling hole plug, 26 - Reaction chamber sampling hole plug, 212 - Amplification liquid sampling hole, 213 - First microchannel, 214 - Upper section hole of the sample and lysis solution sampling hole, 221 - Middle section hole of the sample and lysis solution sampling hole, 222 - Second microchannel, 223 - Upper chamber of the liquid storage chamber, 233 - Third microchannel, 234 - Lower chamber of the liquid storage chamber, 235 is the detection chamber. Detailed implementation manners

[0047] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0048] As Figure 1 shown, this solution adopts a fully enclosed structure design for the nucleic acid rapid test strip detection microfluidic chip, realizing full sealing during a single sample addition, effectively solving the problem of the risk of high-concentration nucleic acid leakage during the nucleic acid rapid detection process and when dealing with waste after the nucleic acid rapid detection; and adopting a solution where the temperature control component, the flow control component, and the test strip are each a subsystem. Not only integrates the lysis function, nucleic acid amplification function, and nucleic acid detection function, separates the lysis function and nucleic acid amplification function in time and space, but also can precisely control the temperature and time during the lysis process and amplification process, effectively ensuring the activity of biological reagents while ensuring the optimal lysis temperature, and the biochemical reaction environments during the lysis process and amplification process can also reach their respective optima, improving the effect and accuracy of nucleic acid rapid detection to a certain extent; at the same time, it also reduces the overall usage and long-term usage costs of users, and can flexibly adapt to changes in the number of people or samples for home nucleic acid rapid detection.

[0049] 1) System composition

[0050] The fully enclosed nucleic acid rapid test strip detection microfluidic portable system consists of two subsystems. The solution of using a temperature control component, namely a portable multi-channel high-precision temperature control system, and a nucleic acid rapid test strip detection microfluidic chip composed of a flow control component and a test strip as one subsystem respectively, will reduce the overall usage and long-term usage costs of users, and can flexibly adapt to the changes in the number of people or samples for home nucleic acid rapid detection, such as Figure 1 shown, which are the portable multi-channel high-precision temperature control system 1 and the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 respectively. Among them, the temperature adjustment actuator 11 of the portable multi-channel high-precision temperature control system 1 (composed of multi-channel temperature adjustment devices, heat insulation materials between multi-channel temperature adjustment actuators, and a support structure, each channel can perform independent local high-precision temperature control, and can avoid the problem of uneven spatial distribution of the temperature field during multi-channel temperature control to ensure temperature accuracy), contacts a specific part of the fully enclosed nucleic acid rapid test strip detection microfluidic chip 1. This specific part is the vertical mapping area of the reaction chamber 231 on the surface far from the sample and lysis buffer loading holes, and only locally heats the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2, which can minimize the power requirement and the requirement for the external dimension of the portable multi-channel high-precision temperature control system 1.

[0051] To solve the problem of the risk of high-concentration nucleic acid leakage during the nucleic acid rapid detection process and when dealing with waste after the nucleic acid rapid detection, a fully enclosed structure design is adopted. The structure of the fully enclosed nucleic acid rapid test strip detection microfluidic chip is as Figure 2 shown. The upper layer 21, the middle layer 22, and the lower layer 23 of the fully enclosed nucleic acid rapid test strip detection microfluidic chip are prepared by high-precision numerical control machining or thermocompression molding methods, and the material is plastic with good biological performance and optical transparency; and after preparation, they are sealed into a whole by means of thermocompression or ultrasonic welding or chemical reagent treatment followed by ultraviolet irradiation or adhesive bonding or bolt fastening, etc.

[0052] In order to integrate the lysis function, nucleic acid amplification function, and nucleic acid detection function, the lysis function and nucleic acid amplification function are spatially and temporally separated. The overall structure cross-sectional view of the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 is as Figure 3As shown in the figure, in the upper layer 21 of the present invention, an amplification reaction reservoir chamber 211 (sealed after being plugged) for placing nucleic acid amplification reaction is provided, and in the lower layer 23, a reaction chamber 231 for initially placing samples and lysis solution (sealed after being plugged) is provided. The amplification reaction reservoir chamber 211 is sealed by an amplification solution sampling hole plug 25, and the reaction chamber 231 is sealed by a reaction chamber sampling hole plug 26. Among them, the amplification solution sampling hole plug 25 and the reaction chamber sampling hole plug 26 are made of soft materials such as rubber or silica gel and have certain mechanical properties. They are in the shape of a cylinder and are in interference fit with the inner wall surface of the corresponding sampling hole to achieve sealing. The amplification reaction reservoir chamber 211 is formed by sealing the middle layer of the multi-layer microfluidic chip through the amplification solution sampling hole 212 (through hole, located in the upper layer of the multi-layer microfluidic chip) to form a bottom-sealed reservoir chamber, and its structure is different from that of the reaction chamber 231, mainly considering that there is no (little) residual liquid after operation, and before operation, the liquid will be maintained within the rectangular area of the amplification reaction reservoir chamber 211 due to the action of surface tension. The sunken type (blind hole structure) of the reaction chamber 231 is set considering the needs of heat transfer and flow control.

[0053] The upper layer 21 of the fully enclosed nucleic acid rapid test strip detection microfluidic chip is as Figure 4 shown in the figure. Among them, the amplification solution is added through the amplification solution sampling hole 212, and the sample and lysis solution are added in the early stage through the upper section hole 214 of the sample and lysis solution sampling hole, and the amplification solution is added to the amplification reaction reservoir chamber 211; the first microchannel 213 is used to connect the amplification reaction reservoir chamber 211 and the upper section hole 214 of the sample and lysis solution sampling hole. After the sample lysis is completed, the amplification solution is transported to the reaction chamber 231 through the upper section hole 214 of the sample and lysis solution sampling hole by shaking.

[0054] As Figure 5 shown in the figure is the structure of the middle layer of the fully enclosed nucleic acid rapid test strip detection microfluidic chip. The middle section hole 221 of the sample and lysis solution sampling hole and the upper section hole 214 of the sample and lysis solution sampling hole form the sample and lysis solution sampling hole for initially transporting the sample and lysis solution to the reaction chamber 231 and transporting the amplification solution after the lysis is completed; the second microchannel 222 connects the middle section hole 221 of the sample and lysis solution sampling hole and the upper chamber 223 of the reservoir chamber, and when the reaction chamber 231 transports the solution after the lysis and amplification reaction is completed to the reservoir chamber, the air in the reservoir chamber is transported to the middle section hole 221 of the sample and lysis solution sampling hole through the second microchannel 222 to ensure the smooth progress of the solution transfer process.

[0055] As Figure 6The structure of the lower layer of the fully enclosed nucleic acid rapid test strip detection microfluidic chip is shown. Among them, in the reaction chamber 231 in the early stage, the sample and the lysis solution are mixed and lysed by heating. Then, through the structures arranged in the upper layer 21 and the middle layer 23, the amplification solution is transported to the reaction chamber 231 for amplification to complete the processing of the sample. The total volume of the liquid in the reaction chamber is 5 - 50 μL; the processed sample is transported to the lower chamber 235 of the liquid storage chamber through the third microchannel 233. The lower chamber of the liquid storage chamber is connected to the detection chamber 235. A nucleic acid rapid test strip 24 is arranged in the detection chamber 235, and the processed sample in the liquid storage chamber is detected by the nucleic acid rapid test strip 24.

[0056] As Figure 7 The structure of the portable multi-channel high-precision temperature control system 1 is shown. Among them, it includes the temperature adjustment execution device 11 of the portable multi-channel high-precision temperature control system 1; the sensing module, including: a temperature sensor and a supporting high-precision analog-to-digital converter ADC; a microcontroller; a serial port touch screen; a DC-DC buck module; the power supply module, including: a DC switching power supply and a rechargeable battery power supply (with a charging interface and circuit) module; the power amplifier circuit, including: the power amplifier circuits of heating devices, refrigeration devices, and cooling fans; the temperature adjustment devices, including: heating devices, refrigeration devices, and cooling fans.

[0057] The temperature adjustment execution device 11 in the portable multi-channel high-precision temperature control system 1 is composed of multi-channel temperature adjustment devices, heat insulation materials between the multi-channel temperature adjustment execution devices, metal blocks, and a support structure. Each channel can perform independent high-precision temperature control and can avoid the problem of uneven spatial distribution of the temperature field during multi-channel temperature control to ensure the temperature control accuracy;

[0058] The heat-conducting metal block, that is, the material of the metal block is a high heat-conductivity metal such as copper or aluminum, used to balance the temperature field, and the temperature sensor is placed inside the metal block;

[0059] The sizes of the heat-conducting metal block, heating execution element, and refrigeration execution element of the portable multi-channel high-precision temperature control system 1 are the sizes that match the local temperature control area of the fully enclosed nucleic acid rapid test strip detection microfluidic chip after being calculated by heat transfer theory and optimized by experiments according to the temperature control requirements;

[0060] The heat insulation material between the multi-channel temperature adjustment execution devices in the temperature adjustment execution device 11 of the portable multi-channel high-precision temperature control system 1 is a lightweight porous heat insulation material or a fibrous heat insulation material, and the material of the support structure is a high-temperature resistant and flame-retardant material;

[0061] The support structure in the temperature adjustment execution device 11 of the portable multi-channel high-precision temperature control system 1 has a structure for positioning and clamping the fully enclosed nucleic acid rapid test strip detection microfluidic chip;

[0062] The main controller of the portable multi-channel high-precision temperature control system 1 is a microcontroller, which has built-in temperature control programs, serial port touch screen communication programs, and start / stop control programs;

[0063] The touch screen of the portable multi-channel high-precision temperature control system 1 is a serial port touch screen, which has built-in temperature control parameter configuration programs and human-machine interaction interfaces, start / stop control programs and human-machine interaction interfaces, data display programs and human-machine interaction interfaces, and data saving and exporting programs and human-machine interaction interfaces;

[0064] The heating actuator of the portable multi-channel high-precision temperature control system 1 is a PI film heater of a specific size (or other heating elements with fast response speed during heating), and the refrigeration actuator is a high-temperature resistant semiconductor refrigeration chip of a specific size, with a heat sink and a fan that match its power. The heating actuator and the refrigeration actuator are closely combined together. Although the semiconductor refrigeration chip acts as a heater by changing the electrode performance, working for a long time at a high cracking temperature will damage its service life;

[0065] The temperature control detection element of the portable multi-channel high-precision temperature control system 1 is a high-precision platinum thermistor or thermocouple and a high-precision analog-to-digital converter with SPI bus communication or I2C bus communication. The sensor is placed inside the heat-conducting metal block near the upper surface; the power supply mode of the portable multi-channel high-precision temperature control system 1 has two modes: rechargeable battery power supply and external mains power supply;

[0066] Adopt a scheme in which the temperature control component, the flow control component, and the test strip are each a subsystem. In terms of functionality, the temperature control component can not only achieve temperature control and time control for the cracking process and the constant temperature amplification process, but also achieve temperature control and time control for the cracking process and the side-temperature cycle amplification process. In terms of accuracy, the temperature control component can achieve high-precision time control by using the built-in timer, counter, high-precision crystal oscillator, and program algorithm of the microcontroller; and can achieve high-precision temperature control by using the built-in high-speed input / output ports and high-precision program algorithm of the microcontroller. As Figure 8 shown is the typical temperature curve when the portable multi-channel high-precision temperature control system conducts temperature control. Figure 8 As shown in (a) of it is the temperature-time curve of typical cracking plus constant temperature amplification, where T 0 is the ambient temperature, T 1 is the cracking temperature, T 2 is the constant temperature amplification temperature, t 1 is the time of the cracking process (including the transition time of temperature regulation and the working time of temperature stabilization), and t2 is the time of the constant temperature amplification process (including the transition time of temperature regulation and the working time of temperature stabilization); Figure 8As shown in (b) therein is the temperature-time curve of typical lysis plus temperature-variable amplification, where T 0 is the ambient temperature, T 1 is the lysis temperature, T 3 is the denaturation temperature in temperature-variable amplification, T 4 is the annealing temperature in temperature-variable amplification, T 5 is the extension temperature in temperature-variable amplification, t 1 is the time of the lysis process (including the transition time of temperature regulation and the working time of temperature stabilization), and t2 is the time of the temperature-variable amplification process (including the transition time of temperature regulation and the working time of temperature stabilization during the temperature variation).

[0067] 2) Working principle of the above system:

[0068] Adopting the scheme that the temperature control component, the flow control component and the test strip are respectively a subsystem, and isolating the integration of the lysis function and the nucleic acid amplification function in time can effectively ensure the activity of the biological reagent while using the optimal lysis temperature, and can also ensure that the biochemical reaction environment is in its respective optimum. As Figure 9 shown is the process principle that after the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 completes the lysis process and the amplification process, the reaction liquid is transferred into the liquid storage chamber, and the reaction liquid is brought into contact with the nucleic acid rapid test strip. It is shown that the user pinches the front and back of the dotted box with the thumb and index finger and shakes the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 (the process is similar to the reset operation of a mercury thermometer before measuring body temperature). The liquid in the reaction chamber is transferred into the liquid storage chamber within the enclosed space inside the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 under the action of capillary force, gravity and externally applied centrifugal force in fluid mechanics. The liquid transferred into the liquid storage chamber is adsorbed by the nucleic acid rapid test strip, and the nucleic acid detection function is realized through the immunochromatography method of the test strip.

[0069] As Figure 10 shown is the schematic diagram of the enclosed space formed inside the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 and the flow condition. The reaction chamber 231, the second gas microchannel 222, the liquid microchannel 233 and the liquid storage chamber constitute a connected and enclosed space.

[0070] As Figure 11 and Figure 12Shown is the mechanical analysis of the process of the reaction liquid in the reaction chamber inside the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 transferring into the liquid storage chamber. According to the basic theory of capillary action in fluid mechanics, it needs to be analyzed in two cases based on different ranges of the liquid contact angle. Because there are two types of liquid surface shapes in the microchannel caused by capillary action, the first case is a concave surface, and the second case is a convex surface. And all the following analyses need to meet the following assumptions: (1) The cross-sectional shape of the microchannel is square; (2) The liquid can wet the microchannel wall; (3) The four sides of the liquid contact in the square microchannel can be assumed to be semi-circular; (4) Temperature changes are not considered.

[0071] For the first case where the capillary liquid surface is concave, an analysis model as shown in Figure 11 can be established. According to the basic theory of mechanics, the force situation in the y-axis direction can be obtained. At this time, the resultant force Fy in the y-axis direction is:

[0072]

[0073] In the formula, θ, contact angle, °;

[0074] h, the height of the liquid column corresponding to above the microchannel, m; d, the side length of the square microchannel with a cross-sectional shape, m; γ, the surface tension of the liquid, N / m; ρ, the liquid density, kg / m 3 ; g y , the component of the gravitational acceleration in the y-axis direction, m / s 2 ; a y , the component of the centrifugal acceleration in the y-axis direction, m / s 2 ; m, the mass of the liquid affected by the centrifugal force, kg.

[0075] Inference 1: The liquid in the microchannel is always subject to a resultant force along the negative y-axis direction shown in the figure, which in turn causes the liquid in the reaction chamber to enter the liquid storage chamber along the negative y-axis direction through the microchannel and be adsorbed by the nucleic acid rapid test strip.

[0076] For the second case where the capillary liquid surface is concave, an analysis model as shown in Figure 12 can be established. According to the basic theory of mechanics, the force situation in the y-axis direction can be obtained. At this time, the resultant force Fy in the y-axis direction is:

[0077]

[0078] In the formula, θ, contact angle, °; h, the height of the liquid column corresponding to above the microchannel, m; d, the side length of the square microchannel with a cross-sectional shape, m; γ, the surface tension of the liquid, N / m; ρ, the liquid density, kg / m 3 ; g y, Component of the acceleration due to gravity in the y-axis direction, m / s 2 ; a y , Component of the centripetal acceleration in the y-axis direction, m / s 2 ; m, Mass of the liquid affected by the centripetal force, kg.

[0079] For the situation in formula (2), when not affected by the centripetal force F cf and the resultant force Fy = 0, the critical value of the height h of the liquid column corresponding to the upper part of the microchannel is:

[0080]

[0081] Inference 2: When the fully enclosed nucleic acid rapid test strip detection microfluidic chip is not affected by the centripetal force, the critical height of the liquid column in the microchannel that keeps the liquid from moving along the negative y-axis direction shown in the figure satisfies formula (3); when the fully enclosed nucleic acid rapid test strip detection microfluidic chip is affected by an increased centripetal force, it will cause the liquid in the reaction chamber to enter the liquid storage chamber along the negative y-axis direction through the microchannel and be adsorbed by the nucleic acid rapid test strip.

[0082] The working principle of the portable multi-channel high-precision temperature control system 1 is to configure the temperature control function through the parameter configuration function built in the serial port touch screen. Place the reaction chamber part of the fully enclosed nucleic acid rapid test strip detection microfluidic chip on the temperature adjustment execution device 11 of the portable multi-channel high-precision temperature control system. Then start the start / stop function built in the serial port touch screen and send the control signal to the microcontroller through the serial port; the temperature control and time control programs built in the microcontroller, after receiving the configuration instruction and the start / stop instruction, collect the temperature of the fully enclosed nucleic acid rapid test strip detection microfluidic chip through the temperature sensor and the supporting high-precision analog-to-digital converter ADC. The control signal is output by the temperature control program built in the microcontroller to the power amplifier circuits of the heating device, the refrigeration device, and the cooling fan, and then drives the heating device, the refrigeration device, and the cooling fan to work to achieve temperature control, and at the same time achieve time control under the time control program built in the microcontroller.

[0083] 3) Specific working steps of the system:

[0084] This solution adopts a fully enclosed structural design for the nucleic acid rapid test strip detection microfluidic chip, achieving full enclosure during a single sample addition, effectively solving the problem of the risk of high-concentration nucleic acid leakage during the nucleic acid rapid detection process and when dealing with waste after the nucleic acid rapid detection. Moreover, a solution is adopted where the temperature control component, the flow control component, and the test strip are each a subsystem. This not only integrates the functions of lysis, nucleic acid amplification, and nucleic acid detection, separates the lysis function and the nucleic acid amplification function in terms of time and space, but also enables precise control of the temperature and time during the lysis process and the amplification process. It can effectively ensure the activity of biological reagents while ensuring the optimal lysis temperature, and the biochemical reaction environments during the lysis process and the amplification process can also reach their respective optima, improving the effect and accuracy of nucleic acid rapid detection to a certain extent. At the same time, it also reduces the overall and long-term usage costs for users and can flexibly adapt to changes in the number of people or samples for home nucleic acid rapid detection.

[0085] Its specific working steps are mainly the following 6 steps:

[0086] Step 1: Horizontally place the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2, and open the amplification solution sample addition hole plug 25 and the reaction chamber sample addition hole plug 26;

[0087] Step 2: Add samples (samples, lysis solution), and cover the reaction chamber sample addition hole plug 26, add amplification solution, and cover the amplification solution sample addition hole plug 25;

[0088] Step 3: Place the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2 on the portable multi-channel high-precision temperature control system 1 for lysis;

[0089] Step 4: Press down the amplification solution sample addition hole plug 25 and pull up the reaction chamber sample addition hole plug 26, and the amplification solution enters the reaction chamber for amplification;

[0090] Step 5: After the amplification reaction ends, remove the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2, pinch and shake the chip to allow the amplified liquid to come into full contact with the nucleic acid rapid test strip;

[0091] Step 6: Horizontally place the fully enclosed nucleic acid rapid test strip detection microfluidic chip 2, wait for the test strip to show the test result, and properly handle the chip to ensure biological safety.

[0092] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A fully enclosed nucleic acid rapid test strip detection microfluidic chip, characterized in that, it includes: an upper layer, a middle layer and a lower layer sealed to form a fully enclosed nucleic acid rapid test strip detection microfluidic chip; wherein the upper layer is provided with an amplification solution loading hole, an amplification reaction storage chamber, a first microchannel and an upper section hole of the lysis solution loading hole. The amplification reaction storage chamber is communicated with the upper section hole of the sample and lysis solution loading hole through the first microchannel. The amplification reaction storage chamber is communicated with the amplification solution loading hole, and an amplification solution loading hole plug is correspondingly arranged inside the amplification solution loading hole; the middle layer is provided with a middle section sample and lysis solution loading hole, a second microchannel and an upper chamber of the storage chamber; the middle section hole of the sample and lysis solution loading hole is communicated with the upper chamber of the storage chamber through the second microchannel. The upper section hole of the sample and lysis solution loading hole is communicated with the middle section hole of the sample and lysis solution loading hole to form a sample and lysis solution loading hole, and a reaction chamber loading hole plug is correspondingly arranged inside the sample and lysis solution loading hole; the lower layer is provided with a reaction chamber, a third microchannel, a lower chamber of the storage chamber and a detection chamber. The reaction chamber is communicated with the lower chamber of the storage chamber through the third microchannel. The detection chamber is communicated with the lower chamber of the storage chamber and a nucleic acid rapid test strip is arranged inside. The lower chamber of the storage chamber is communicated with the upper chamber of the storage chamber to form a storage chamber; the middle section hole of the sample and lysis solution loading hole and the upper section hole of the sample and lysis solution loading hole form a sample and lysis solution loading hole for transporting the sample and lysis solution to the reaction chamber in the early stage and transporting the amplification solution after lysis is completed; the second microchannel communicates the middle section hole of the sample and lysis solution loading hole with the upper chamber of the storage chamber, and when the reaction chamber transports the solution after lysis and amplification reaction to the storage chamber, the air in the storage chamber is transported to the middle section hole of the sample and lysis solution loading hole through the second microchannel to ensure the smooth progress of the solution transfer process; in the early stage, the sample and lysis solution are mixed in the reaction chamber and lysed by heating. Then, through the structures arranged in the upper layer and the middle layer, the amplification solution is transported to the reaction chamber for amplification to complete the processing of the sample; the processed sample is transported to the lower chamber of the storage chamber through the third microchannel. The lower chamber of the storage chamber is communicated with the detection chamber, and a nucleic acid rapid test strip is arranged in the detection chamber. The processed sample in the storage chamber is detected by the nucleic acid rapid test strip.

2. The microfluidic chip according to claim 1, characterized in that: the amplification solution loading hole plug and the reaction chamber loading hole plug are made of rubber or silica gel materials.

3. A portable system based on the fully enclosed nucleic acid rapid test strip detection microfluidic chip according to any one of claims 1-2, characterized in that, it includes: a portable multi-channel high-precision temperature control system and a fully enclosed nucleic acid rapid test strip detection microfluidic chip, wherein the portable multi-channel high-precision temperature control system includes: a temperature adjustment execution device, a sensing module, a microcontroller, a touch screen, a step-down module, a power supply module, a power amplifier circuit; The power supply module is connected to the microcontroller and the touch screen through the buck module respectively to supply power to the microcontroller and the touch screen respectively; the power supply module is connected to the power amplifier circuit; the sensing module, the microcontroller, the power amplifier circuit and the temperature adjustment device are connected in sequence; the temperature adjustment device is in contact with the metal block to achieve temperature control of the metal block, and the sensing module is arranged corresponding to the metal block; the microcontroller is connected to the touch screen; the microcontroller is used to control the temperature adjustment device through the power amplifier circuit according to the temperature data obtained by the sensing module, and transmit the temperature data to the touch screen for storage and display; The temperature adjustment execution device is in contact with a plurality of fully enclosed nucleic acid rapid test strip detection microfluidic chips to achieve portable temperature control of the fully enclosed nucleic acid rapid test strip detection microfluidic chips.

4. The portable system according to claim 3, wherein: The temperature adjustment execution device includes a multi-channel temperature adjustment device, a metal block, heat insulation materials between the multi-channel temperature adjustment execution devices and a support structure, and the metal block is made of copper or aluminum material.

5. The portable system according to claim 3, wherein: The sensing module includes a temperature sensor and an ADC module, wherein the temperature sensor is fixed near the surface inside the metal block to obtain the temperature data of the metal block.

6. The portable system according to claim 3, wherein: The power amplifier circuit includes a heating power amplifier circuit, a refrigeration power amplifier circuit and a cooling fan power amplifier circuit.

7. The portable system according to claim 3, wherein: The temperature adjustment device includes a heating device, a refrigeration device and a cooling fan, wherein the heating device uses a PI film heater, and the refrigeration device uses a high-temperature resistant semiconductor refrigeration chip; wherein the heating device and the refrigeration device are attached and in contact with the metal block.

8. The portable system according to claim 3, wherein: The power supply module includes a DC switching power supply and a rechargeable battery, wherein the DC switching power supply is connected to the mains.

9. The portable system according to claim 3, wherein: The buck module uses a DC-DC buck module.

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