CN116203093B - Electrochemical microfluidic biochip for automated enzyme-labeled substrate-catalyzed amplification of hybrid DNA signals and its application - Google Patents

Electrochemical microfluidic biochip for automated enzyme-labeled substrate-catalyzed amplification of hybrid DNA signals and its application Download PDF

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CN116203093B
CN116203093B CN202111445810.4A CN202111445810A CN116203093B CN 116203093 B CN116203093 B CN 116203093B CN 202111445810 A CN202111445810 A CN 202111445810A CN 116203093 B CN116203093 B CN 116203093B
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李长明
刘峰
张嫄媛
邹卓
史转转
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Suzhou University of Science and Technology
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Abstract

The invention discloses an electrochemical microfluidic biochip for amplifying hybridization DNA signals by an automatic enzyme-labeled catalytic substrate and application thereof, wherein the biochip comprises a reagent supply unit, a microfluidic device and a waste liquid collecting device, the reagent supply unit is connected with an inlet of the microfluidic device, the waste liquid collecting device is connected with an outlet of the microfluidic device, a nucleic acid probe is modified on the surface of a sensing electrode, a nucleic acid sample to be detected is hybridized with the nucleic acid probe, then a streptavidin nucleic acid capture probe 2 is hybridized with the nucleic acid sample to be detected and combined with the surface of the electrode, finally, the biotin-labeled electrochemical active enzyme is combined with the surface of the electrode by the biological affinity between biotin and streptavidin, or the sample to be detected is marked, and the catalytic substrate is changed into an electrochemical active product, so that signals are amplified and detected on the electrode.

Description

Electrochemical microfluidic biochip for amplifying hybridization DNA signal by using automatic enzyme-labeled catalytic substrate and application thereof
Technical Field
The invention relates to the field of electrochemical detection, in particular to an electrochemical microfluidic biochip for amplifying hybridization DNA signals by using an automatic enzyme-labeled catalytic substrate, a method for detecting nucleic acid by using the biochip and application thereof.
Background
One of the key steps in constructing an electrochemical immunosensor is the selection of an appropriate probe immobilization method. The most widely used method is microsphere-based immobilization techniques when probes are physically adsorbed or covalently bound to the surface of polystyrene microspheres with magnetic cores. Although this approach is highly sensitive, it does not provide the relevant immunoreagent with a controllable spatial resolution, thereby limiting its use in biochips. Another alternative is to use electropolymerized conductor polymers as the matrix for the immobilized immunoreagent. Following the pioneering work of fossa, immobilization of biomolecules such as enzymes, DNA, antibodies and even whole cells in conductive polymers has been widely used to fabricate biosensors, including immunosensors. In order to improve the detection sensitivity, antibodies in the enzyme-linked immunosorbent assay can be marked by a DNA functionalized nanostructure, and the DNA marked functionalized material can realize signal amplification by polymerase chain reaction, hybridization chain reaction or rolling circle amplification technology, and by the technology, the sensitivity of the immune reaction can be improved by a plurality of orders of magnitude compared with that of the traditional enzyme-linked immunosorbent assay. In the ELISA method based on DNA signal amplification, the amplification degree of the catalytic hairpin DNA probe self-assembly reaction and the hybridization chain reaction is limited, and the polymerase chain reaction has high signal amplification degree, but the reaction process requires strict heating and cooling processes, so that the expansion application of the polymerase chain reaction is limited. In comparison, the rolling circle amplification technique has unique advantages in that isothermal amplification is employed to achieve amplification of signal molecules 10 5 to 10 9, even on the order of an exponential. But also require temperature control equipment and thus limit use to the territory and environment.
Therefore, there is a need for a product that has high sensitivity, requires no additional equipment, requires low storage conditions, and can be used in a variety of environments.
Disclosure of Invention
In view of the above, one of the purposes of the present invention is to provide an electrochemical microfluidic biochip for amplifying hybridization DNA signals by using an automated enzyme-labeled catalytic substrate, and the other purpose of the present invention is to provide an application of the microfluidic biochip in manufacturing an automated detection device.
In order to achieve the above purpose, the present invention provides the following technical solutions:
an electrochemical microfluidic biochip for amplifying hybridization DNA signals by an automatic enzyme-labeled catalytic substrate, wherein the electrochemical microfluidic biochip comprises a reagent supply unit, a microfluidic device and a waste liquid collecting device, the reagent supply unit is connected with an inlet of the microfluidic device, and the waste liquid collecting device is connected with an outlet of the microfluidic device;
The microfluidic device body is a microfluidic channel, the microfluidic channel is provided with at least one sensing electrode for detecting electrochemical signals, and a nucleic acid probe for specifically identifying nucleic acid to be detected is modified on the sensing electrode;
The reagent supply unit comprises a cleaning solution reservoir, a nucleic acid reservoir to be tested, a substrate reservoir, a streptavidin nucleic acid probe reservoir, a biotinylated electrochemical active enzyme reservoir and a waste liquid reservoir;
During detection, the nucleic acid fragment to be detected is sent to the sensing electrode through a microfluidic channel to be complementarily matched and combined with the nucleic acid probe 1 on the sensing electrode, a cleaning solution is introduced to clean and leave a matched substance, then the nucleic acid fragment is combined with the electrochemical enzyme-labeled nucleic acid probe 2, the cleaning solution is introduced to clean, a base solution is introduced to convert a labeled electrochemical active enzyme catalytic substrate into an electrochemical active substance, and the electrochemical active substance is detected by an electrochemical method;
Or during detection, firstly, the nucleic acid fragment to be detected is marked by electrochemical enzyme, then is sent to a sensing electrode through a microfluidic channel to be complementarily paired and combined with a nucleic acid probe 1 on the sensing electrode, a cleaning solution is introduced to clean the unpaired substances and unreacted enzyme labels, only the paired substances are left, a base solution is introduced to convert the marked electrochemical active enzyme catalytic substrate into the electrochemical active substance, the electrochemical active substance is detected by an electrochemical method, and an electrochemical signal can be amplified by adjusting the concentration of the base solution or increasing the reaction time.
Preferably, the microfluidic channel is composed of one or more sample injection channels, the sample injection channels are provided with at least one sub-channel, and the sensing electrode of the modified nucleic acid probe is arranged on the sub-channel.
In the invention, preferably, a microfluidic cleaning unit is also connected between the reservoir and the outlet of the microfluidic channel, one end of the microfluidic cleaning unit is connected with the outlet of the microfluidic channel, and the other end is connected with the waste liquid reservoir.
Preferably, the biochip is a microfluidic device for address management.
Preferably, the cleaning solution is not limited to PBS solution, the electrochemically active enzyme is not limited to alkaline phosphatase, and the substrate is not limited to PBS solution containing aminophenyl phosphate.
Preferably, the material of the sensing electrode is, but not limited to, metal oxide, metal carbide, conductive plastic, conductive polymer, carbon material or a combination or mixture thereof.
Preferably, the nucleic acid probes of the present invention are, but are not limited to, nucleic acid sequences that detect cancer, chronic disease or pathogenic microorganisms.
In the invention, preferably, the reaction liquid collected by the substrate storage can be recycled by electrochemical reverse reaction and then used continuously.
Preferably, the microfluidic device is prepared by printing, 3-D printing, micromachining, electrodeposition or vacuum deposition.
In the invention, preferably, the control system of the microfluidic device adopts an ARM architecture STM32 microprocessor as a core chip building circuit.
In the invention, electrochemical enzyme can be modified on the nucleic acid or fragment to be detected and complementarily paired with the nucleic acid probe on the sensing electrode, a cleaning solution is introduced to clean the nucleic acid or fragment to be detected and the substrate is introduced to enable the electrochemical active enzyme mark marked on the nucleic acid or fragment to be detected and captured by the nucleic acid probe to catalyze the substrate to be converted into electrochemical active substance, the electrochemical detection can be carried out by an electrochemical method, and the electrochemical signal can be amplified by adjusting the concentration of the primer or increasing the reaction time.
2. The electrochemical microfluidic biochip is applied to the preparation of portable timely diagnostic medical devices.
The invention has the beneficial effects that the invention discloses a sensor for amplifying hybridization DNA signals by enzyme-labeled catalytic substrates, the sensor adopts a nucleic acid probe modified on the surface of an electrode, then the sensor is hybridized with a nucleic acid sample to be detected, then the sensor is hybridized with a streptavidin-type nucleic acid capture probe 2, finally the biotin-type electrochemical active enzyme is combined on the surface of the electrode through the bioaffinity effect between biotin and streptavidin by a method of labeling the sample, and the catalytic substrate without electrochemical activity is changed into an electrochemical active product, so that the signals are detected through the electrode. Based on such principle, a highly sensitive electrochemical biochip employing substrate enzyme catalytic labelling to amplify hybridized DNA signals can also be fabricated for simultaneous detection of a variety of major diseases or chronic conditions based on nucleic acid probes. Compared with the traditional method for fixing the biological molecules, the method has the advantages that the substrate concentration is increased or the detection time is prolonged, the detection sensitivity is greatly improved, the sample consumption is reduced, and the detection cost is greatly reduced. And the product can be used by people and regions, has low requirement on storage conditions, can be used in various environments, and is basically not influenced by temperature and humidity.
The sensor and the biochip detection device thereof of the invention are composed of a microfluidic sample acquisition unit, a sensing array unit and a detection unit. The invention has high sensitivity and small amount of required samples, and expands the detection means.
Drawings
In order to make the objects, technical solutions and advantageous effects of the present invention more clear, the present invention provides the following drawings for description:
FIG. 1 is a schematic diagram of a sensor construction (arrows indicate reagent flow direction);
FIG. 2 is a block diagram of a microfluidic sample acquisition unit;
FIG. 3 is a schematic diagram of the detection;
FIG. 4 is a schematic illustration of alkaline phosphatase-catalyzed hydrolysis of aminophenyl phosphate to para-aminophenol;
FIG. 5 is the oxidation of para-aminophenol to para-benzoquinone imine;
FIG. 6 shows differential impulse response curves of different concentrations of nucleic acid samples to be tested;
FIG. 7 is a stability test chart of an electrochemical sensor;
FIG. 8 is a diagram showing a selective test of an electrochemical sensor, wherein (a) is a fully complementary target DNA, (b) is a single base mismatched target DNA, (c) is a multi-base mismatched target DNA, and (d) is a non-complementary target DNA.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and specific examples, which are not intended to limit the invention, so that those skilled in the art may better understand the invention and practice it.
Example 1, enzyme-labeled catalytic substrate amplification of hybridized DNA Signal electrochemical microfluidic biochip
The structure of the electrochemical microfluidic biochip for amplifying hybridization DNA signals by using enzyme-labeled catalytic substrates is shown in figure 1. As shown in the figure, the sensor comprises a reagent supply unit 1, a microfluidic device 2 and a waste liquid collection device 3, wherein the reagent supply unit 1 is connected with an inlet of the microfluidic device 2, and the waste liquid collection device 3 is connected with an outlet of the microfluidic device 4.
The main body of the microfluidic device 2 is a microfluidic channel 5 for conveying a nucleic acid sample to be detected, a substrate, a streptavidin nucleic acid capture probe 2, biotinylated electrochemical enzyme and a cleaning solution;
The microfluidic device further comprises a processor, an ARM architecture STM32 microprocessor is used as a core chip to build a circuit to control the injection pump, the circuit is connected through a signal output line, dynamic adjustment of samples and other additives is achieved, the performance is high, the cost is low, the power consumption is low, and the operation software uses an intelligent algorithm to deeply excavate detection data. The control unit is shown in a system block diagram in fig. 2, wherein the injection pump and the processor are powered by a power supply, the injection pump is controlled by the processor through a stepping motor driver, and detection signals are finally transmitted to the man-machine interface through the processor. The automatic control unit circuit of the microfluidic device 2 is shown in fig. 3.
The microfluidic channel is provided with at least one sensing electrode 6 and a counter electrode 7 for detecting electrochemical signals, and nucleic acid probes for specifically identifying nucleic acids to be detected are modified on the sensing electrode. Preferably, the microfluidic channel is composed of one or more sample injection channels, the sample injection channels are provided with at least one sub-channel, sensing electrodes for modifying the nucleic acid probes are arranged on the sub-channels, the plurality of sample injection channels and the plurality of sub-channels are arranged to form an array structure, and the sensing electrodes at different positions modify different nucleic acid probes so as to realize high-flux detection and realize the microfluidic device through address management.
The reagent supply unit comprises a cleaning solution reservoir 8, a nucleic acid reservoir 9 to be tested, a substrate reservoir 10, a nucleic acid capture probe 2 reservoir 11 with streptavidin and an electrochemical enzyme reservoir 12 with biotinylation, wherein the cleaning solution, the nucleic acid to be tested, the substrate, the nucleic acid capture probe 2 with streptavidin and the electrochemical enzyme with biotinylation are respectively stored, and DNA in the nucleic acid capture probe 2 reservoir with streptavidin can be complementarily paired with partial gene sequences of the nucleic acid to be tested. Preferably, the cleaning solution is a PBS solution, the electrochemical enzyme is alkaline phosphatase, and the substrate is an aminophenyl phosphate-containing PBS solution.
Further, a microfluidic cleaning unit 12 is further connected between the waste liquid collecting device 3 and the outlet of the microfluidic device 2, one end of the microfluidic cleaning unit is connected with the outlet of the microfluidic device 2, and the other end is connected with the waste liquid collecting device 3, and a pipeline communicated with the substrate storage 10 is further arranged for recycling and reusing the substrate. The oxidation reaction product benzoquinone imine (PQI) is reduced under the action of an electrode in the reaction liquid, so that an electroactive product p-aminophenol (PAP) is generated and conveyed back to a substrate storage, the detection sensitivity is improved, and the sample consumption is reduced.
The material of the sensing electrode in the embodiment can be metal, metal oxide, metal carbide, conductive plastic, conductive polymer, carbon material or their composition or mixture, printing, 3-D printing, micromachining, electrodeposition or vacuum deposition preparation
In this embodiment, the nucleic acid probe designs a specific recognition sequence according to a specific detected cancer, chronic disease or pathogenic microorganism.
During detection, the nucleic acid fragment to be detected is sent to the sensing electrode through a microfluidic channel to be complementarily matched and combined with the nucleic acid probe 1 on the sensing electrode, a cleaning solution is introduced to clean and leave a matched substance, then the nucleic acid fragment is combined with the electrochemical enzyme-labeled nucleic acid probe 2, the cleaning solution is introduced to clean, a base solution is introduced to convert a labeled electrochemical active enzyme catalytic substrate into an electrochemical active substance, and the electrochemical active substance is detected by an electrochemical method;
Or during detection, firstly, the nucleic acid fragment to be detected is marked by electrochemical enzyme, then is sent to a sensing electrode through a microfluidic channel to be complementarily paired and combined with a nucleic acid probe 1 on the sensing electrode, a cleaning solution is introduced to clean the unpaired substances and unreacted enzyme labels, only the paired substances are left, a base solution is introduced to convert the marked electrochemical active enzyme catalytic substrate into the electrochemical active substance, the electrochemical active substance is detected by an electrochemical method, and an electrochemical signal can be amplified by adjusting the concentration of the base solution or increasing the reaction time.
Example 2 methods for detecting nucleic acid markers Using the biochip
The principle of the method for detecting the nucleic acid marker by using the biochip is shown in fig. 3, and the specific steps are as follows:
a method for detecting nucleic acid based on electrochemical signals, comprising the steps of:
1) The method comprises the specific steps of modifying a nucleic acid probe for specifically recognizing nucleic acid to be detected on a sensing electrode, namely dripping a PBS solution of the nucleic acid probe with the concentration of 1 mug/mL on the surface of the sensing electrode, incubating for 2 hours at room temperature, and then washing the surface of the electrode by using the PBS solution to remove the nucleic acid probe which is not modified on the surface of the electrode, wherein the sequence of the nucleic acid probe is 5'-ttttttttttttttt TCCGTCCCACCTCATGTGT-3'.
2) During detection, the nucleic acid or fragment to be detected is sent to the sensing electrode through the microfluidic channel to be complementarily paired and combined with the nucleic acid probe on the sensing electrode, a cleaning solution is introduced to clean and leave paired substances, then the streptavidin nucleic acid probe 2 is introduced, the streptavidin nucleic acid probe 2 is combined with the nucleic acid or fragment to be detected to clean and remove unbound molecules, and electrochemical enzyme is fixed on the sensing electrode in combination with biotinylated electrochemical enzyme, so that the electrochemical active enzyme marked on the nucleic acid or nucleic acid fragment to be detected captured by the nucleic acid probe can catalyze the substrate to be converted into electrochemical active substances, the electrochemical active substances can be detected by an electrochemical method, and the electrochemical signal can be amplified by adjusting the concentration of a base solution or increasing the reaction time.
2) In this example, a sample containing a nucleic acid to be tested (5'-tggtggcgtctctaacacatgaggtgggacgga-3') is introduced into a microfluidic device modified with a nucleic acid probe, after incubation for 30min at room temperature, the nucleic acid sample not bound to the nucleic acid probe is washed with PBS, then 1. Mu.g/mL of streptavidin-coated nucleic acid capture probe 2 (5'-tttttttttttttttttttttACCACCGCAGAGAT-3') is introduced into the microfluidic device and incubated for 30min, after washing with PBS to remove unbound streptavidin-coated nucleic acid capture probe 2, and then 1. Mu.g/mL of biotinylated alkaline phosphatase is introduced into the microfluidic device and incubated for 30min at room temperature, and the alkaline phosphatase not bound to the electrode surface is washed off with PBS. Then, a substrate is input for enzyme-catalyzed reaction, wherein the substrate is PBS solution containing aminophenyl phosphate (PAPP). In the detection, alkaline phosphatase (ALP) was enzymatically converted to p-aminophenyl phosphate (PAPP), as shown in FIG. 4, which is an electrochemically active substance, and voltage was applied to the working electrode based on the reference electrode, and PAP was oxidized to p-benzoquinone imine (PQI), to generate electrons, as shown in FIG. 5, and the presence of ALP was detected by the current value in the electrochemical measurement by two reactions, i.e., the enzymatic reaction and the redox reaction.
The nucleic acid samples to be tested were tested at different concentrations, respectively 0M and 10 -18 M、10-16 M、10-14 M、10-12 M、10-10 M、10-8 M、10-6 M, according to the same procedure as described above, and the results are shown in FIG. 6. The results show that the method for detecting nucleic acid has the advantage of high sensitivity.
The sensors constructed were left for 5 days, 10 days and 15 days, respectively, and then were tested, and their response signals were reduced by only 4.35%, 8.79% and 11.74% from the initial state, and the results are shown in fig. 7. The results show that the stability of the constructed sensor is very good.
The constructed sensor was used to detect full-complement target DNA, single base mismatched target DNA (mismatch at position 10 of target sequence), multiple base mismatched target DNA (mismatch at positions 5, 10, 15, and 20 of target sequence), non-complementary target DNA (using random sequences), respectively, to evaluate the selectivity of the gene sensor, and the results are shown in fig. 8. The results show that the constructed sensor can distinguish non-complementary target DNA, multi-base mismatched target DNA and single-base mismatched target DNA.
In this embodiment, the sensing electrode may be a blank electrode, and the nucleic acid probe is first immobilized and then detected during detection.
Example 3 construction of automated inspection device
The biochip prepared in example 1 is combined with a control device to construct an automatic detection device, and the detection control device comprises a sensing electrode signal acquisition module, a microfluidic sample injection and flow control module, an electric signal amplification module, an analog-to-digital conversion processing module, a wireless signal transmission module and a data processing module. The STM32 microprocessor adopting the ARM architecture is used as a core chip to build a circuit, has high performance, low cost and low power consumption, and is used for collecting electrochemical signals, amplifying electric signals, carrying out analog-to-digital conversion processing, transmitting wireless signals and carrying out data processing, and transmitting the signals into a mobile phone terminal to realize automatic electrochemical rapid detection.
The above-described embodiments are merely preferred embodiments for fully explaining the present invention, and the scope of the present invention is not limited thereto. Equivalent substitutions and modifications will occur to those skilled in the art based on the present invention, and are intended to be within the scope of the present invention. The protection scope of the invention is subject to the claims.

Claims (1)

1.电化学微流控生物芯片在制成便携式及时诊断医疗装置中的应用,其特征在于:所述电化学微流控生物芯片包括试剂供给单元、微流控装置和废液收集装置,试剂供给单元与微流控装置的入口连接,废液收集装置与微流控装置的出口连接;1. Application of an electrochemical microfluidic biochip in a portable timely diagnostic medical device, characterized in that: the electrochemical microfluidic biochip comprises a reagent supply unit, a microfluidic device and a waste liquid collection device, the reagent supply unit is connected to the inlet of the microfluidic device, and the waste liquid collection device is connected to the outlet of the microfluidic device; 所述微流控装置主体为微流控通道,所述微流控通道设置有至少一个检测电化学信号的传感电极,所述传感电极上修饰有特异识别待测核酸的核酸探针;所述微流控装置由印刷、3-D打印、微加工、电沉积或真空沉积制备,所述微流控装置的控制系统采用ARM架构STM32微处理器作为核心芯片搭建电路;核酸探针为检测癌症、慢性病或病原微生物的核酸序列;The main body of the microfluidic device is a microfluidic channel, and the microfluidic channel is provided with at least one sensing electrode for detecting electrochemical signals, and the sensing electrode is modified with a nucleic acid probe for specifically identifying the nucleic acid to be detected; the microfluidic device is prepared by printing, 3-D printing, micromachining, electrodeposition or vacuum deposition, and the control system of the microfluidic device uses an ARM architecture STM32 microprocessor as a core chip to build a circuit; the nucleic acid probe is a nucleic acid sequence for detecting cancer, chronic diseases or pathogenic microorganisms; 所述试剂供给单元包括清洗溶液储存器、待测核酸储存器、底物储存器、链酶亲和素化核酸探针储存器、生物素化的电化学活性酶储存器和废液储存器;所述生物素化的电化学活性酶储存器中为碱性磷酸酶溶液;所述底物储存器中为含氨基苯基磷酸酯的PBS溶液;所述废液储存器与微流控通道的出口之间还连接有微流控清洗单元,微流控清洗单元一端与微流控通道出口连接,一端与废液储存器连接,还设置有与底物储存器连通的管道,用于底物回收并循环利用;所述生物芯片为地址化管理的微流控装置;所述清洗溶液为PBS液,所述电化学活性酶为碱性磷酸酶;所述底物为含氨基苯基磷酸酯的PBS溶液;The reagent supply unit comprises a cleaning solution storage, a nucleic acid storage to be tested, a substrate storage, a streptavidin nucleic acid probe storage, a biotinylated electrochemically active enzyme storage and a waste liquid storage; the biotinylated electrochemically active enzyme storage contains an alkaline phosphatase solution; the substrate storage contains a PBS solution containing aminophenyl phosphate; a microfluidic cleaning unit is connected between the waste liquid storage and the outlet of the microfluidic channel, one end of the microfluidic cleaning unit is connected to the outlet of the microfluidic channel, and the other end is connected to the waste liquid storage, and a pipeline connected to the substrate storage is also provided for substrate recovery and recycling; the biochip is an address-managed microfluidic device; the cleaning solution is PBS solution, the electrochemically active enzyme is alkaline phosphatase; the substrate is a PBS solution containing aminophenyl phosphate; 所述清洗单元收集的回收至底物储存器的反应液用电化学逆向反应回收后继续使用;The reaction solution collected by the cleaning unit and recycled to the substrate storage is recycled by electrochemical reverse reaction and then continuously used; 检测时,将待测核酸片段通过微流控通道送至传感电极处,与传感电极上的核酸探针1互补配对结合;通入清洗溶液洗清洗,留下配对物质;然后与电化学酶标的核酸探针2结合,通入清洗溶液洗清洗;通入底液,使标记的电化学活性酶催化底物转化为电化学活性物质,用电化学方法进行检测;电化学信号可通过调高底液浓度或增长反应时间放大;During detection, the nucleic acid fragment to be detected is sent to the sensing electrode through the microfluidic channel, and is complementary and paired with the nucleic acid probe 1 on the sensing electrode; a cleaning solution is introduced to wash it, leaving the paired substance; then it is combined with the nucleic acid probe 2 labeled with an electrochemical enzyme, and a cleaning solution is introduced to wash it; a base solution is introduced to make the labeled electrochemically active enzyme catalyze the substrate into an electrochemically active substance, and the detection is performed by an electrochemical method; the electrochemical signal can be amplified by increasing the concentration of the base solution or increasing the reaction time; 或者检测时,首先将待测核酸片段用电化学酶标记,然后通过微流控通道送至传感电极处,与传感电极上的核酸探针1互补配对结合;通入清洗溶液洗清洗掉未配对物质与未反应的酶标,仅留下配对物质;通入底液,使标记的电化学活性酶催化底物转化为电化学活性物质,用电化学方法进行检测;电化学信号可通过调高底液浓度或增长反应时间放大;Alternatively, during detection, the nucleic acid fragment to be detected is first labeled with an electrochemical enzyme, and then sent to the sensing electrode through a microfluidic channel to complement and pair with the nucleic acid probe 1 on the sensing electrode; a cleaning solution is introduced to wash away unpaired substances and unreacted enzyme labels, leaving only paired substances; a base solution is introduced to allow the labeled electrochemically active enzyme to catalyze the substrate into an electrochemically active substance, and the detection is performed using an electrochemical method; the electrochemical signal can be amplified by increasing the concentration of the base solution or increasing the reaction time; 所述传感电极的材料为金属、金属氧化物、金属碳化物、导电塑料、导电聚合物、碳材料或其组合物或混合物。The material of the sensing electrode is metal, metal oxide, metal carbide, conductive plastic, conductive polymer, carbon material or a combination or mixture thereof.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1499195A (en) * 2002-10-31 2004-05-26 惠普开发有限公司 Microflow system for analyzing nucleic acid
JP2010156605A (en) * 2008-12-26 2010-07-15 Mitsubishi Chemical Medience Corp Electrical analysis method

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1278821A4 (en) * 2000-05-03 2005-11-09 Jen Gau Jr BIOLOGICAL IDENTIFICATION SYSTEM WITH INTEGRATED SENSOR CHIP
WO2005095262A1 (en) * 2004-04-01 2005-10-13 Nanyang Technological University Microchip and method for detecting molecules and molecular interactions
ES2658169T3 (en) * 2009-08-02 2018-03-08 Qvella Corporation Cell concentration, capture and lysis devices and their method of use
US8702959B2 (en) * 2009-12-31 2014-04-22 Ramot At Tel-Aviv University Ltd. System and method for detecting a substance in liquid
US20130040374A1 (en) * 2010-04-28 2013-02-14 Panasonic Corporation Chemical sensor
CN102539494B (en) * 2012-01-12 2014-07-30 福建医科大学 Amperometric DNA (deoxyribonucleic acid) electrochemical sensor based on protein controlled assembling interface
KR102270811B1 (en) * 2020-06-30 2021-06-30 (주)바이오제네시스 Electrochemical biosensor based on hybrid graphene electrode

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1499195A (en) * 2002-10-31 2004-05-26 惠普开发有限公司 Microflow system for analyzing nucleic acid
JP2010156605A (en) * 2008-12-26 2010-07-15 Mitsubishi Chemical Medience Corp Electrical analysis method

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