Detection chip, equipment and method for detecting HIV RNA (Human Immunodeficiency Virus Ribonucleic Acid) in saliva

Abstract

The invention provides a detection chip, device and method for detecting HIV RNA in saliva, the detection chip comprises a chip substrate, a plurality of electric signal transmission interfaces are integrated on the chip substrate, the detection chip further comprises a reaction electrode, a differential electrode and a reference electrode, the surface of the reaction electrode is modified with nucleic acid aptamer molecules, and the surface of the differential electrode is modified with nucleic acid aptamer molecules. The detection module is used for generating a detection electric signal according to specific binding of nucleic acid aptamer molecules and HIV RNA; the differential electrode is a blank electrode and is used for deducting background signals generated by non-specific molecules in an added sample solution and a to-be-detected solution and amplifying a detection electric signal through the differential amplification circuit; the reference electrode is used for providing stable reference potential; the reaction electrode, the differential electrode and the reference electrode are electrically connected with an electric signal transmission interface respectively. According to the invention, the HIV RNA in the saliva is detected based on field effect transistor biological detection and by adopting a differential signal amplification technology, so that the effects of accurately detecting trace HIV RNA in the saliva, improving the yin-yang coincidence rate and simplifying the detection operation are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of HIV detection, and in particular to a detection chip, device and method for detecting HIV RNA in saliva. Background Art

[0002] HIV testing is a medical test that detects HIV viral components (such as antibodies, antigens, nucleic acids, etc.) or related immune indicators in human blood, body fluids or tissues to determine whether a person is infected with the AIDS virus. It is a medical test method for monitoring the course of the disease and evaluating the effectiveness of treatment. HIV testing technologies mainly include antibody testing (such as rapid test strips, ELISA and other IgG / IgM antibody detection methods, the window period of this method is 3-6 weeks), antigen / antibody combined detection (the fourth-generation technology simultaneously detects p24 antigen and antibody, the window period of this method can be shortened to 2-4 weeks after infection), and RNA detection (direct detection of viral nucleic acid, the window period of this method is 1-2 weeks, suitable for early diagnosis and confirmation of infant infection). Existing antibody detection and antigen / antibody combined detection technologies may have false positives due to their long window period, and require confirmation tests to verify. Therefore, they cannot effectively identify the virus in the very early stages of infection (within 7-10 days). HIV RNA testing, with the help of real-time fluorescence quantitative PCR, rapid nucleic acid technology (such as isothermal amplification technology TMA) and other methods, can detect the virus at the very early stage of 7-10 days after infection, especially providing a critical window period advantage for post-exposure prevention (PEP) and mother-to-child transmission intervention.

[0003] However, all of the above methods rely on the collection of blood samples (serum / plasma). Their invasive operation not only increases the risk of cross-infection between doctors and patients, but also limits their promotion and application in home testing, primary care, and large-scale screening scenarios due to the invasive nature of blood collection. Although recent studies have shown that HIV RNA and antibodies are also present in the saliva (oral mucosal exudate) of HIV-infected people (penetrating into the saliva through the oral mucosal capillaries), which makes saliva testing have the advantage of non-invasive collection, the existing salivary HIV antibody detection technology has a decrease in detection specificity and an increase in false positive rate due to the extremely low concentration of HIV antibodies in saliva (only 1 / 100 to 1 / 1000 of blood), the high proportion of water in the saliva matrix, the presence of antibody degradation factors such as proteases, and the complex composition. This leads to core technical bottlenecks such as low detection accuracy and insufficient positive-negative coincidence rate. In addition, existing methods for detecting HIV RNA in saliva, such as real-time fluorescence quantitative PCR or isothermal amplification technology TMA, take more than 30 minutes to detect and are heavily dependent on professional operation and complex equipment, making it difficult to meet the application requirements of rapid and simplified detection in instant detection scenarios.

[0004] Therefore, there is a need for a detection chip, detection device, and detection method that can achieve high-accuracy detection of trace amounts of HIV RNA in saliva and make detection simpler and more convenient. Summary of the Invention

[0005] The present invention provides a detection chip, device, and method for detecting HIV RNA in saliva. These chips are primarily designed to address the long window period and invasive collection requirements of existing HIV detection methods, as well as the low accuracy, time consumption, and high operational expertise required of existing salivary HIV antibody detection technologies. These chips achieve the goal of accurately detecting trace amounts of HIV RNA in saliva, improving the positive / negative coincidence rate, and simplifying the detection process.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] A detection chip for detecting HIV RNA in saliva includes a chip substrate with several electrical signal transmission interfaces integrated thereon. The chip substrate is also provided with a reaction electrode, a differential electrode, and a reference electrode. The reaction electrode is surface-modified with nucleic acid aptamer molecules for generating a detection electrical signal based on the specific binding of the nucleic acid aptamer molecules to HIV RNA; the differential electrode is a blank electrode for subtracting background signals generated by nonspecific molecules in the added sample solution and the solution to be tested; the reference electrode is for providing a stable reference potential; and the reaction electrode, differential electrode, and reference electrode are each electrically connected to one of the electrical signal transmission interfaces.

[0008] The detection chip adopts a dual-channel differential circuit. The detection electrical signal output constitutes a sensor channel, and the background signal output constitutes a reference channel. By comparing the channel signal difference between the reaction electrode and the differential electrode, the background noise of HIV RNA detection in saliva is eliminated.

[0009] In a further embodiment, the dosage of the nucleic acid aptamer molecule that specifically binds to HIV RNA is 0.01 to 10 μM.

[0010] The sequences of nucleic acid aptamer molecules that specifically bind to HIV RNA include but are not limited to:

[0011] 5'-CCTGTACTGGGTCTCTCTGG-3' (SEQ ID NO: 1);

[0012] 5'-CACAACAGACGGGCACACACTTGA-3' (SEQ ID NO: 2);

[0013] 5'-CTCTCTCCTTCTAGCCTC-3' (SEQ ID NO: 3).

[0014] A further solution is that a reaction tank is further provided on the chip substrate, and the reaction tank accommodates the reaction electrode, the differential electrode and the reference electrode.

[0015] The chip substrate is made of one of PET, glass or silicon dioxide materials and is integrated with a microfluidic channel for automatic injection, filtration and reaction of the sample solution and the solution to be tested.

[0016] The reaction tank is made of PDMS or PMMA material, and is used to reduce non-specific binding when containing the sample solution and the solution to be tested.

[0017] A further solution is that the reaction electrode and the differential electrode are both made of at least one material selected from the group consisting of gold, silver, copper, titanium, chromium, carbon materials, or conductive polymer materials.

[0018] When detecting HIV RNA in saliva, the reaction electrode is connected to a biomolecular probe, and the biomolecular probe is one of a DNA single strand, a two-dimensional DNA nanostructure, and a three-dimensional DNA nanostructure.

[0019] A further solution is that the reference electrode uses solid silver chloride and contacts the sample solution and the test solution through the microfluidic channel to ensure the stability of the reference potential; the switching state of the transistor sensor is controlled by regulating the reference potential.

[0020] A detection device for detecting HIV RNA in saliva uses the detection chip for detecting HIV RNA in saliva, comprising a transistor sensor, a signal processing module, and a control module. A reaction electrode is connected to the gate of the transistor sensor via an electrical signal transmission interface, and is used to output a detection electrical signal generated by the specific binding of a nucleic acid aptamer molecule to HIV RNA to the transistor sensor in real time. A differential electrode is connected to the differential circuit input end of the transistor sensor via another electrical signal transmission interface. The differential circuit is used to filter background noise and amplify the detection electrical signal based on the background signal, and output a differential amplified signal. The signal processing module is used to convert the differential amplified signal into a digital signal and output it to the control module. The control module is provided with a reference value, is used to compare the digital signal value with the reference value, and output a detection signal curve based on the comparison result. The detection signal curve is used to determine whether HIV RNA in a test solution is negative or positive.

[0021] A further solution is to further include a communication module, wherein the control module establishes a communication connection with the mobile terminal via the communication module, and is used to send the detection data of HIV RNA in the test solution to the mobile terminal.

[0022] A further solution is that the transistor sensor adopts a field effect transistor, which is a metal oxide FET, a silicon FET, a graphene FET or a transition metal dichalcogenide-based FET.

[0023] A method for detecting HIV RNA in saliva, applied to the aforementioned detection device for detecting HIV RNA in saliva, comprising:

[0024] S1: Collect the sample solution and the solution to be tested, put the sample solution and the solution to be tested into a virus buffer tube, press them several times to mix them, and then take them out.

[0025] S2: Connect the detection chip to the detection device via the electrical signal transmission interface and then power on the system.

[0026] S3: A certain amount of buffer solution in the virus buffer tube is taken out and dripped into the reaction tank of the detection chip. After waiting for 10 minutes to allow the captured RNA to reach a certain amount, the detection device outputs a detection signal curve.

[0027] S4: judging whether HIV RNA in the test solution is negative or positive according to the detection signal curve.

[0028] A further solution is that the HIV RNA detection method in step S3 includes:

[0029] S31: Apply a certain gate voltage to put the transistor sensor in an on state.

[0030] S32: When the nucleic acid aptamer molecule specifically binds to HIV RNA on the reaction electrode through the biomolecular probe, the surface potential of the electrode is changed, and the detection signal voltage is output after signal processing by the detection device to form the detection signal curve.

[0031] S33: When the captured RNA reaches a certain amount, if a voltage output signal exceeding a reference value is detected, it indicates that the corresponding sample solution and the test solution contain HIV RNA; if it does not exceed the reference value, it indicates that the corresponding sample solution and the test solution are negative or their HIV RNA content is lower than the minimum detection line set by the detection equipment.

[0032] It can be seen that the present invention has the following beneficial effects:

[0033] 1. The present invention is based on the principle of biological detection technology of field effect transistors and adopts differential signal amplification technology to detect HIV RNA in saliva. If the saliva sample contains HIV RNA, the nucleic acid aptamer probe specifically binds to the HIV RNA, and combined with the charge-sensitive characteristics of the liquid gate extended gate field effect transistor, the field effect transistor sensor outputs a detection signal, which can detect HIV RNA in saliva as low as the international unit (IU / ml) level. Compared with traditional antibodies, nucleic acid aptamers have higher binding affinity and thermal stability, and field effect transistors directly reflect the concentration of target molecules through changes in surface potential, thereby combining high sensitivity with specificity to achieve the detection of trace RNA.

[0034] 2. Based on existing transistor detection equipment, the present invention adopts differential electrodes and signal processing modules. The differential circuit can significantly reduce background noise and improve the signal-to-noise ratio. Compared with the direct sampling detection method in the process of detecting HIV RNA in saliva, it amplifies the signal of target RNA, increases detection accuracy, and avoids false negatives or missed detections due to weak signals.

[0035] 3. The present invention detects HIV RNA in saliva, making saliva sampling safer and avoiding the risk of infection for testers. At the same time, saliva collection and RNA detection are simple and rapid, and can be applied to home self-testing.

[0036] 4. The present invention adopts a chip integrated design. You only need to insert the detection chip into the detection equipment to power on and start the detection. The detection operation is simple and portable, and the cost of the chip and equipment is low. The detection results can be directly sent to the mobile terminal on the user side through the network, so that the detection results can be quickly fed back to the person being tested.

[0037] 5. The detection chip and device for detecting HIV RNA in saliva provided by the present invention achieve highly sensitive, highly specific, and portable detection of HIV RNA in saliva while taking into account cost-effectiveness. They can become an important tool for early HIV screening and efficacy monitoring and have broad market prospects.

[0038] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of a detection chip for detecting HIV RNA in saliva according to an embodiment of the present invention.

[0040] Figure 2 This is a circuit diagram of a detection device for detecting HIV RNA in saliva according to an embodiment of the present invention.

[0041] Figure 3It is a schematic diagram of the connection between the detection chip and the detection device according to an embodiment of the present invention.

[0042] Figure 4 Schematic diagram of a method for detecting HIV RNA in saliva according to an embodiment of the present invention.

[0043] Figure 5 This is a schematic diagram of a positive result of detecting HIV RNA in saliva according to an embodiment of the present invention.

[0044] Figure 6 Schematic diagram of a negative result of HIV RNA detection in saliva according to an embodiment of the present invention.

[0045] Figure 7 This is a flow chart of a method for detecting HIV RNA in saliva according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] An embodiment of a detection chip for detecting HIV RNA in saliva

[0048] See also Figure 1 The embodiment of the present invention relates to a detection chip for detecting HIV RNA in saliva, including a chip substrate 6, on which are integrated several electrical signal transmission interfaces 5. The chip substrate 6 is also provided with a reaction electrode 1, a differential electrode 3 and a reference electrode 2. The surface of the reaction electrode 1 is modified with a nucleic acid aptamer molecule, which is used to generate a detection electrical signal based on the specific binding of the nucleic acid aptamer molecule to HIV RNA; the differential electrode 3 is a blank electrode, which is used to detect the background signal generated by the addition of a sample solution and non-specific molecules in the test solution; the reference electrode 2 is used to provide a stable reference potential; the reaction electrode 1, the differential electrode 3, and the reference electrode 2 are respectively electrically connected to an electrical signal transmission interface 5.

[0049] The detection chip 100 uses a dual-channel differential circuit 21. The detection electrical signal output constitutes a sensor channel, and the background signal output constitutes a reference channel. By comparing the channel signal difference between the reaction electrode and the differential electrode, the background noise of HIV RNA detection in saliva is eliminated.

[0050] Specifically, the detection chip 100 of this embodiment is a transistor-type detection chip, wherein the reaction electrode 1 is modified with a nucleic acid aptamer molecule that specifically binds to HIV RNA, while the differential electrode 3 is unmodified with any molecule. The reference electrode 2 is used to control the on / off switching of the transistor. When using the detection chip 100 to detect sample solutions and test solutions, when HIV RNA is present in the sample solution or the test solution, it specifically binds to the nucleic acid aptamer molecule on the reaction electrode 1, generating the detection electrical signal. Simultaneously, nonspecific adsorption at the differential electrode 3 will also generate a background signal.

[0051] In this embodiment, the dosage of the nucleic acid aptamer molecule that specifically binds to HIV RNA is 0.01 to 10 μM.

[0052] The sequences of nucleic acid aptamer molecules that specifically bind to HIV RNA include but are not limited to:

[0053] 5'-CCTGTACTGGGTCTCTCTGG-3' (SEQ ID NO: 1);

[0054] 5'-CACAACAGACGGGCACACACTTGA-3' (SEQ ID NO: 2);

[0055] 5'-CTCTCTCCTTCTAGCCTC-3' (SEQ ID NO: 3).

[0056] In this embodiment, a reaction tank 4 is further provided on the chip substrate 6 , and the reaction tank 4 accommodates the reaction electrode 1 , the differential electrode 3 and the reference electrode 2 .

[0057] The chip substrate 6 is made of one of PET, glass or silicon dioxide materials, and is integrated with a microfluidic channel for automatic injection, filtration and reaction of sample solutions and test solutions.

[0058] Specifically, the inner wall of the microfluidic channel described in this embodiment is coated with an anti-adsorption coating to reduce mucin interference. The detection process can be completed in less than 10 minutes, including: saliva pretreatment → RNA capture → signal conversion → differential signal output, without manual operation.

[0059] The reaction tank 4 is made of PDMS or PMMA material to reduce non-specific binding when containing the sample solution and the test solution.

[0060] In this embodiment, the reaction electrode 1 and the differential electrode 3 are both made of at least one material selected from the group consisting of gold, silver, copper, titanium, chromium, carbon materials, and conductive polymer materials.

[0061] When detecting HIV RNA in saliva, the reaction electrode 1 is connected to a biomolecular probe, wherein the biomolecular probe is one of a DNA single strand, a two-dimensional DNA nanostructure, and a three-dimensional DNA nanostructure.

[0062] Specifically, in this embodiment, after the biomolecular probe captures the target RNA, the surface charge density of reaction electrode 1 changes, generating a detection signal that is transmitted to the FET gate. Furthermore, when HIV RNA binds to the biomolecular probe, the double layer potential at the reaction electrode 1-solution interface changes, effectively applying an additional voltage to the gate.

[0063] Specifically, in this embodiment, the differential electrode 3 is connected to the source or drain of another symmetrical field-effect transistor to form a differential amplifier circuit to suppress common-mode interference. Alternatively, the differential electrode 3 is connected to a current mirror circuit to offset temperature drift by matching transistor parameters. The differential electrode 3 can eliminate background current caused by nonspecific adsorption (such as mucin in saliva). The background signal output by the differential amplifier circuit is used to extract the net change value, which can significantly improve sensitivity.

[0064] In this embodiment, the reference electrode 2 is made of solid silver chloride and is in contact with the sample solution and the test solution through the microfluidic channel to ensure the stability of the reference potential; the switching state of the transistor sensor 20 is controlled by regulating the reference potential.

[0065] Specifically, in this embodiment, the reference electrode 2 forms a stable double electric layer with the solution, and an external bias circuit provides a reference voltage to the gate to ensure that the channel is in a critical state of on or off.

[0066] Specifically, the switching control logic of the reference electrode 2 on the field effect transistor FET in this embodiment is: when the target RNA is not bound, the reference electrode 2 maintains the gate potential higher than the threshold voltage, at which time the field effect transistor FET is turned on; after binding, the interface potential changes.

[0067] Specifically, in the present embodiment, in HIV RNA detection, the reference electrode 2 can be switched on and off by timing control. When in the initial state, the reference electrode 2 applies a forward bias, so that the FET is in the subthreshold region, and the current I ds The transistor's original leakage current, Ids, decreases sharply, triggering the logic circuit to output a "shutdown" signal. The above method is merely illustrative and not the only switch control method.

[0068] An embodiment of a detection device for detecting HIV RNA in saliva

[0069] See also Figure 2-4An embodiment of the present invention relates to a detection device for detecting HIV RNA in saliva, which uses the detection chip for detecting HIV RNA in saliva, including a transistor sensor 20, a signal processing module, and a control module 40. The reaction electrode 1 is electrically connected to the gate of the transistor sensor 20 via an electrical signal transmission interface 5, and is used to output the detection electrical signal generated by the specific binding of the nucleic acid aptamer molecule to HIV RNA to the transistor sensor 20 in real time; the differential electrode 3 is connected to the input end of the differential circuit 21 of the transistor sensor 20 via another electrical signal transmission interface 5, and the differential circuit 21 is used to filter the background noise and amplify the signal of the detection electrical signal according to the background signal, and output a differential amplified signal; the signal processing module is used to convert the differential amplified signal into a digital signal and output it to the control module 40. The control module 40 is provided with a reference value, and is used to compare the digital signal value with the reference value, and output a detection signal curve based on the comparison result, and the detection signal curve is used to determine whether the HIV RNA in the test solution is negative or positive.

[0070] In this embodiment, a communication module 50 is further included. The control module 40 establishes a communication connection with the mobile terminal 60 via the communication module 50 , so as to send the detection data of HIV RNA in the test solution to the mobile terminal 60 .

[0071] Specifically, the communication module 50 of this embodiment adopts a wireless communication module 50 , which establishes wireless communication with the mobile terminal 60 , such as WiFi, Bluetooth, etc., to perform wireless data transmission.

[0072] Specifically, the communication module 50 of this embodiment may also be a wired communication module 50 , such as being connected to the on-site analyzer via a data line 300 to achieve wired transmission of detection data.

[0073] Specifically, the detection device 200 of this embodiment further includes a housing, in which the transistor sensor 20 and an integrated circuit board consisting of a signal processing module, a control module 40 and a communication module 50 are fixedly installed.

[0074] In this embodiment, the transistor sensor 20 uses a field effect transistor, which is a metal oxide FET, a silicon FET, a graphene FET, or a transition metal dichalcogenide-based FET.

[0075] Specifically, the transistor sensor 20 of this embodiment is a liquid gate type extended gate field effect transistor sensor 20, and the signal processing module includes a differential amplifier circuit, a filter circuit and an analog-to-digital conversion module 30. The field effect transistor sensor 20 is regulated by a silver chloride electrode to realize the on / off control of the field effect transistor. The HIV RNA probe is modified on the extended gate (i.e., the reaction electrode 1) to specifically bind to the HIV RNA. At the same time, a differential electrode 3 is used and a differential circuit 21 is used to subtract background noise based on surface adsorption or binding from non-specific molecules; the differential amplifier circuit further amplifies and filters the differential signal after filtering out the background noise; the filter circuit is used to filter out other interference, such as power frequency interference, to ensure high resolution of the signal; by configuring the analog-to-digital conversion module 30 with a high sampling rate, the analog signal is converted into a digital signal to achieve high-precision detection of the signal.

[0076] Example of a method for detecting HIV RNA in saliva

[0077] See also Figures 5 to 7 The present invention relates to a method for detecting HIV RNA in saliva, which is applied to the detection device for detecting HIV RNA in saliva, comprising:

[0078] S1: Collect a sample solution and a solution to be tested, and put the sample solution and the solution to be tested into a virus buffer tube 400, press them several times to mix them, and then take them out.

[0079] Specifically, the method for collecting the test solution in this embodiment is to collect saliva by wiping the gums back and forth with an oral sampling swab, and then place the collected oral sampling swab into the virus buffer tube 400.

[0080] S2: Connect the detection chip to the detection device 200 via the electrical signal transmission interface 5 and then power on the system.

[0081] S3: A certain amount of buffer solution in the virus buffer tube 400 is taken out and dripped into the reaction tank 4 of the detection chip 100. After waiting for 10 minutes to allow the captured RNA to reach a certain amount, the detection device outputs a detection signal curve.

[0082] Specifically, in this embodiment, 2 drops (about 50 μl) of buffer solution are taken out at a time and dropped into the reaction tank 4 of the detection chip.

[0083] S4: judging whether HIV RNA in the test solution is negative or positive according to the detection signal curve.

[0084] See also Figure 6Specifically, the detection signal curve in this embodiment shows a parabolic dynamic response curve, and the difference signal curve change value exceeds 10 times the baseline noise. A positive result indicates that HIV RNA is detected in the sample, and HIV infection is suspected.

[0085] See also Figure 7 Specifically, the change in the detection signal curve in this embodiment is much less than 10 times the baseline noise. A negative result indicates that no HIV RNA was detected in the sample, but a negative result cannot completely rule out the possibility of infection.

[0086] In this embodiment, the HIV RNA detection method in step S3 includes:

[0087] S31: applying a certain gate voltage to put the transistor sensor 20 into an on state.

[0088] S32: When the nucleic acid aptamer molecule specifically binds to HIV RNA on the reaction electrode 1 through the biomolecular probe, the surface potential of the electrode is changed, and the detection signal voltage is output after signal processing by the detection device to form the detection signal curve.

[0089] S33: When the captured RNA reaches a certain amount, if a voltage output signal exceeding a reference value is detected, it indicates that the corresponding sample solution and the test solution contain HIV RNA; if it does not exceed the reference value, it indicates that the corresponding sample solution and the test solution are negative or their HIV RNA content is lower than the minimum detection line set by the detection device 200.

[0090] Specifically, in this embodiment, when the captured RNA reaches a certain amount (in IU / ml), a voltage output signal exceeding the baseline value (10 times the baseline noise value) is detected, indicating that the sample contains HIV RNA. If it does not exceed the baseline value, it indicates that the sample is negative or the content is below the minimum detection limit of the detection equipment.

[0091] Specifically, the method for preparing the biochip nucleic acid aptamer probe in this embodiment includes:

[0092] a. Add 1 μl of 0.01-10 mM tris(2-formylethyl)phosphine hydrochloride solution to 99 μl of thiol-modified aptamer probe solution (concentration 0.01-10 μM) using a pipette, gently shake to mix, and reduce at room temperature for 1 hour.

[0093] b. Add 100 μl of the solution mixed in the previous step to the electrode surface and incubate at room temperature for 2 hours to allow the nucleic acid aptamer molecules to be fixed and modified on the electrode surface through covalent bonds.

[0094] c. After modification, rinse the electrode surface with phosphate buffer solution to remove unreacted probes and nonspecific adsorbed molecules, and blow dry with nitrogen gas for later use.

[0095] In addition, other raw materials or reagents used in the present invention are all available in the prior art, such as tris(2-formylethyl)phosphine hydrochloride, nucleic acid aptamer probe sequence, phosphate buffer solution, oral sampling swab and virus buffer solution.

[0096] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A detection chip for detecting HIV RNA in saliva, comprising a chip substrate on which a plurality of electrical signal transmission interfaces are integrated, characterized in that: The chip substrate is further provided with: A reaction electrode, a differential electrode, and a reference electrode. The reaction electrode is surface-modified with nucleic acid aptamer molecules for generating a detection electrical signal based on the specific binding of the nucleic acid aptamer molecules to HIV RNA. The differential electrode is a blank electrode for subtracting background signals generated by nonspecific molecules in the added sample solution and the test solution. The reference electrode is used to provide a stable reference potential. The reaction electrode, differential electrode, and reference electrode are each electrically connected to an electrical signal transmission interface. The detection chip adopts a dual-channel differential circuit. The detection electrical signal output constitutes a sensor channel, and the background signal output constitutes a reference channel. By comparing the channel signal difference between the reaction electrode and the differential electrode, the background noise of HIV RNA detection in saliva is eliminated.

2. The detection chip for detecting HIV RNA in saliva according to claim 1, characterized in that: The dosage of the nucleic acid aptamer molecule that specifically binds to HIV RNA is 0.01 to 10 μM; The sequences of nucleic acid aptamer molecules that specifically bind to HIV RNA include but are not limited to: 5′-CCTGTACTGGGTCTCTCTGG-3′; 5'-CACAACAGACGGGCACACACTTGA-3'; 5′-CTCTCTCCTTCTAGCCTC-3′.

3. The detection chip for detecting HIV RNA in saliva according to claim 1, characterized in that: The chip substrate is further provided with a reaction tank, wherein the reaction tank contains the reaction electrode, the differential electrode and the reference electrode; The chip substrate is made of one of PET, glass or silicon dioxide materials, and is integrated with a microfluidic channel for automatic injection, filtration and reaction of the sample solution and the test solution; The reaction tank is made of PDMS or PMMA material, and is used to reduce non-specific binding when containing the sample solution and the solution to be tested.

4. The detection chip for detecting HIV RNA in saliva according to claim 3, characterized in that: The reaction electrode and the differential electrode are both made of at least one material selected from the group consisting of gold, silver, copper, titanium, chromium, carbon materials, or conductive polymer materials; When detecting HIV RNA in saliva, the reaction electrode is connected to a biomolecular probe, and the biomolecular probe is one of a DNA single strand, a two-dimensional DNA nanostructure, and a three-dimensional DNA nanostructure.

5. The detection chip for detecting HIV RNA in saliva according to claim 3, characterized in that: The reference electrode is made of solid silver chloride and contacts the sample solution and the solution to be tested through the microfluidic channel to ensure the stability of the reference potential; the switching state of the transistor sensor is controlled by regulating the reference potential.

6. A detection device for detecting HIV RNA in saliva, characterized in that: The detection chip for detecting HIV RNA in saliva according to any one of claims 1 to 5 comprises: A transistor sensor, a signal processing module, and a control module, wherein a reaction electrode is connected to the gate of the transistor sensor via an electrical signal transmission interface, and is used to output the detection electrical signal generated by the specific binding of a nucleic acid aptamer molecule to HIV RNA to the transistor sensor in real time; a differential electrode is connected to the differential circuit input end of the transistor sensor via another electrical signal transmission interface, and the differential circuit is used to filter background noise and amplify the detection electrical signal according to the background signal, and output a differential amplified signal; the signal processing module is used to convert the differential amplified signal into a digital signal and output it to the control module, and the control module is provided with a reference value, and is used to compare the digital signal value with the reference value, and output a detection signal curve according to the comparison result, and the detection signal curve is used to determine whether the HIV RNA in the test solution is negative or positive.

7. The detection device for detecting HIV RNA in saliva according to claim 6, characterized in that: The control module also includes a communication module, through which the control module establishes a communication connection with the mobile terminal, and is used to send the detection data of HIV RNA in the solution to be tested to the mobile terminal.

8. The detection device for detecting HIV RNA in saliva according to claim 6, characterized in that: The transistor sensor adopts a field effect transistor, which is a metal oxide FET, a silicon FET, a graphene FET or a transition metal dichalcogenide FET.

9. A method for detecting HIV RNA in saliva, characterized in that: A detection device for detecting HIV RNA in saliva as claimed in any one of claims 1 to 8, comprising: S1: Collect a sample solution and a test solution, put them into a virus buffer tube, press them several times to mix them, and then take them out; S2: Connecting the detection chip to the detection device via the electrical signal transmission interface and then powering on the system; S3: A certain amount of buffer solution in the virus buffer tube is taken out and dripped into the reaction tank of the detection chip. After waiting for 10 minutes so that the captured RNA reaches a certain amount, the detection device outputs a detection signal curve; S4: judging whether HIV RNA in the test solution is negative or positive according to the detection signal curve.

10. The method for detecting HIV RNA in saliva according to claim 9, characterized in that: The HIV RNA detection method in step S3 includes: S31: applying a certain gate voltage to turn the transistor sensor on; S32: When the nucleic acid aptamer molecule specifically binds to HIV RNA on the reaction electrode through the biomolecular probe, the surface potential of the electrode is changed, and a detection signal voltage is output after signal processing by a detection device, thereby forming the detection signal curve; S33: When the captured RNA reaches a certain amount, if a voltage output signal exceeding a reference value is detected, it indicates that the corresponding sample solution and the test solution contain HIV RNA; if it does not exceed the reference value, it indicates that the corresponding sample solution and the test solution are negative or their HIV RNA content is lower than the minimum detection line set by the detection equipment.

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