Rapid low-cost remote medical detection platform for laser-induced graphene immunity

Abstract

The invention discloses a rapid low-cost remote medical detection platform for laser-induced graphene immunity, and relates to the technical field of biomedical detection. The platform comprises the following components: a sensor array module, wherein a patterned structure containing four graphene working electrodes, an Ag / AgCl reference electrode and a graphene counter electrode is formed on a polyimide substrate by adopting a CO2 laser engraving technology, a specific antibody is fixed after functionalization of 1-pyrene butyric acid, and the sensor array module is sealed by bovine serum albumin; according to the present invention, the detection cost is greatly reduced by using the laser engraving graphene electrode preparation process, and the multiple antibodies can be specifically fixed by constructing the sensor array module containing the four graphene working electrodes so as to achieve the detection effect. According to the method, synchronous detection of multiple paths of biomarkers such as SARS-CoV-2 nucleocapsid protein, spike protein specific IgM / IgG antibodies and C-reactive protein is realized, the sample detection period can be controlled within 10 minutes, and the detection efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of biomedical detection technology, and in particular to a laser-induced graphene immune rapid and low-cost remote medical detection platform. Background Art

[0002] In today's field of biomedical testing technology, with the frequent outbreaks of infectious diseases and people's growing demand for health monitoring, fast, accurate and convenient medical testing methods are particularly important. Infectious diseases are characterized by rapid spread and wide impact. Early and rapid diagnosis is crucial to controlling the spread and formulating effective treatment plans. At the same time, the modern medical model is gradually shifting towards telemedicine and home health monitoring. This requires that testing technology not only has on-site rapid testing capabilities, but also needs to be able to realize remote data transmission so that doctors can obtain patients' test information in a timely manner and conduct remote diagnosis. However, existing testing technologies still face many challenges in meeting these needs and urgently need new technological breakthroughs and innovations.

[0003] In the field of rapid diagnosis of infectious diseases, the various existing detection technologies have obvious limitations. Although the real-time fluorescence quantitative PCR detection method has high sensitivity and specificity, this technology is heavily dependent on expensive instruments and professional operators. The detection process is complex and has a long cycle. It usually takes several hours or even longer to obtain results, which is difficult to meet the needs of rapid on-site diagnosis. The serological method based on antibody detection, although relatively simple to operate, cannot effectively distinguish between infection status and immune status, lacks the ability to comprehensively evaluate the disease process, and may lead to misdiagnosis or missed diagnosis. In addition, most existing POCT detection equipment can only perform single-indicator detection and cannot realize multi-marker joint analysis. At the same time, these devices generally lack remote data transmission functions, and the test results cannot be uploaded to the telemedicine platform in a timely manner, making it difficult to adapt to the needs of modern telemedicine monitoring. Summary of the Invention

[0004] The purpose of the present invention is to make up for the shortcomings of the existing technology and provide a laser-induced graphene immune rapid and low-cost remote medical detection platform, which can form a patterned electrode structure on a polyimide substrate by adopting CO2 laser engraving technology. The traditional preparation method has the problems of high production cost, complex process, and difficulty in mass production, which seriously restricts the industrialization process of graphene-based biosensors, resulting in high costs for detection platforms based on traditional graphene, which is difficult to meet the needs of primary medical care and large-scale screening. The present invention adopts laser-induced graphene preparation technology, abandoning the high cost and complex process of traditional chemical vapor deposition, redox and other methods. Laser engraving technology can be directly on polyimide substrates. Graphene is generated in situ on an amine substrate, reducing material costs and supporting roll-to-roll mass production to meet large-scale testing needs. Multiple antibodies are immobilized through functionalization to achieve simultaneous detection of multiple biomarkers. Combined with the electrochemical detection module and the wireless transmission and electronic control module, four-channel electrochemical signal simultaneous acquisition and wireless transmission are achieved. At the same time, a standardized sample pretreatment process is established to support direct detection of non-invasive samples such as saliva. The present invention has the advantages of low cost, high-throughput mass production, rapid detection, support for non-invasive sample detection and remote data transmission. It can be widely used in on-site diagnosis of infectious diseases and home health monitoring scenarios, providing technical support for rapid response to public health emergencies.

[0005] To solve the above technical problems, the present invention provides the following technical solutions: a laser-induced graphene immunoassay rapid and low-cost remote medical detection platform, the method comprising the following specific steps: Sensor array module: A patterned structure containing four graphene working electrodes, one Ag / AgCl reference electrode, and one graphene counter electrode was formed on a polyimide substrate using CO2 laser engraving technology. The structure was functionalized with 1-pyrenebutyric acid, then immobilized with specific antibodies and blocked with bovine serum albumin. Electrochemical detection module: Based on differential pulse voltammetry and electrochemical impedance spectroscopy, a double sandwich and indirect immunoassay strategy is used. After incubation of diluted blood or saliva samples, enzyme-labeled antibodies are bound and electrochemical signals are collected in a buffer containing hydroquinone and hydrogen peroxide. Wireless transmission and electronic system module: Based on the Arm Cortex-M4 microcontroller, it integrates a Bluetooth module and signal processing circuit, is powered by a lithium-ion polymer battery, and uses firmware to control detection timing and achieve wireless data transmission; Sample processing module: Blood samples were diluted 1:100 with PBS containing 1.0% BSA, and saliva samples were diluted 1:5 with PBS, and then used directly for sensor array detection.

[0006] Furthermore, the sensor array module forms a patterned structure comprising four graphene working electrodes, one Ag / AgCl reference electrode, and one graphene counter electrode on a polyimide substrate through CO2 laser engraving technology. The laser engraving power is 8.0%, the speed is 15%, and the dots per inch is 1000. The laser engraving process directly converts the porous graphene structure on the PI substrate by precisely controlling the power and speed. The mesoporous design significantly increases the specific surface area, provides more active sites for the adsorption of biomolecules, and improves the detection sensitivity. The specific surface area reaches 1200m 2 / g, the Ag / AgCl reference electrode was electrodeposited in a mixed solution containing 250 mM silver nitrate, 750 mM sodium thiosulfate and 500 mM sodium bisulfite at a current of -0.2 mA for 100 seconds and then drop-casted with FeCl3 solution for 1 minute.

[0007] Furthermore, in the sensor array module, the electrode surface was modified with π-π stacking using a 5.0 mM 1-pyrenebutyric acid (PBA) solution in DMF. After activation with 0.4 M EDC and 0.1 M sulfo-NHS, 250 μg / mL of S1-IgG, S1-IgM, CRP antibody, or 50-fold diluted NP antibody was immobilized via amide bonds, and unreacted sites were blocked with a 2.0% bovine serum albumin solution.

[0008] Furthermore, the electrochemical detection module is based on differential pulse voltammetry (DPV) and open circuit potential electrochemical impedance spectroscopy (EIS), using double sandwich and sandwich detection configurations for SARS-CoV-2 nucleocapsid protein NP and C-reactive protein (CRP), and indirect immunoassay for S1-IgG and S1-IgM.

[0009] Furthermore, in the electrochemical detection module, during the test, the blood sample was diluted 100 times with PBS containing 1.0% BSA, and the saliva sample was diluted 5 times. 10 μL was taken and incubated with the functionalized electrode for 1-10 minutes. The HRP-labeled detection antibody was added and incubated at room temperature for 5 minutes. 1.0 mM H2O2 was added to 0.05 M sodium phosphate buffer containing 2.0 mM hydroquinone HQ, and the amperometric signal was recorded at a potential of -0.2 V relative to Ag / AgCl.

[0010] Furthermore, HRP-labeled detection antibodies were added to the electrochemical detection module, NP detection was diluted 250 times, S1-IgG and S1-IgM were 2.0 mg / mL, and NP detection required an additional incubation with 1.0 mg / mL HRP-goat anti-rabbit IgG for 5 minutes.

[0011] Furthermore, in the electrochemical detection module, the DPV detection conditions are: potential range -0.2~0.6V, pulse width 0.2s, incremental potential 4mV, amplitude 50mV; EIS reaction conditions: frequency range 0.1~10 6 Hz, amplitude 5mV.

[0012] Furthermore, the wireless transmission and electronic system module is based on the STM32L432KC microcontroller and integrates the SPBT3.0DP2 Bluetooth 5.0 module, supports data transmission within a range of 10 meters, adopts the BLE (Bluetooth Low Energy) protocol, and has a transmission rate of 1Mbps. The signal processing circuit is composed of a transimpedance amplifier circuit composed of an AD8605 single op amp and an AD8608 quad op amp. The current detection resolution reaches 1nA. The power supply system uses a 3.7V / 500mAh lithium-ion polymer battery and is equipped with an ISL60002 voltage reference chip. Low power consumption control is achieved through PWM pulse width modulation, with a standby current of less than 10μA and a power consumption of 15mW in continuous detection mode. The PCB board adopts a 4-layer immersion gold process, with a size of 20mm×35mm×7.3mm, an integrated 4-channel 16-bit ADC, a sampling rate of 10kHz, and data is transmitted to the Bluetooth module through the UART interface, supporting real-time reception by the device APP.

[0013] Furthermore, the sample processing module: blood samples are stored in EDTA-containing blood collection tubes, diluted 1:100 with 0.01M PBS containing 1.0% BSA before testing, and 0.05% sodium azide is added to the diluent; saliva samples are collected using a sterile funnel and immediately diluted 1:5 with PBS containing 1.0% BSA after collection, and 0.1% Tween-20 is added to the diluent to enhance protein solubility. All diluted samples are tested within 2 hours.

[0014] Compared with the existing technology, this laser-induced graphene immune rapid and low-cost remote medical detection platform has the following beneficial effects: 1. The present invention greatly reduces the detection cost by adopting a laser-engraved graphene electrode preparation process. At the same time, by constructing a sensor array module containing four graphene working electrodes, it can specifically fix multiple antibodies and realize the simultaneous detection of multiple biomarkers such as SARS-CoV-2 nucleocapsid protein, spike protein-specific IgM / IgG antibodies and C-reactive protein. The sample detection cycle can be controlled within 10 minutes, greatly improving the detection efficiency, providing strong support for the rapid on-site diagnosis of infectious diseases, and can be widely used in rapid response scenarios for public health emergencies.

[0015] 2. By integrating Bluetooth wireless transmission function, the present invention can upload test data to the telemedicine platform in real time, realizing portable remote diagnosis, so that the test results can be transmitted to medical staff in a timely manner, facilitating their remote diagnosis and guiding treatment, thereby improving the efficiency and accessibility of medical services. In addition, the present invention supports direct detection of non-invasive samples such as saliva, reducing patient discomfort, further improving user experience, and providing convenience for home health monitoring of infectious diseases.

[0016] 3. The present invention adopts a laser-induced graphene preparation process, which abandons the high cost and complex processes of traditional chemical vapor deposition, redox and other methods. Laser engraving technology can directly generate graphene in situ on a polyimide substrate, reducing material costs and supporting roll-to-roll mass production to meet large-scale testing needs.

[0017] Other advantages, objects and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be learned from the practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0019] Figure 1 This is a schematic diagram of the structure of a laser-induced graphene immunoassay platform for rapid and low-cost remote medical detection. Figure 2 Flowchart of a laser-induced graphene immunoassay platform for rapid and low-cost remote medical detection. DETAILED DESCRIPTION

[0020] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0021] Example 1 The electrode array was prepared on a 125 μm thick polyimide (PI) film by CO2 laser engraving technology. The engraving parameters were power 8.0%, speed 15%, and resolution 1000 dpi. Four 2 mm × 3 mm mesoporous graphene working electrodes (specific surface area 1200 m 2 / g), a 1mm inner diameter annular Ag / AgCl reference electrode, and a 5mm×5mm graphene counter electrode. The laser engraving process directly transforms the porous graphene structure on the PI substrate by precisely controlling the power and speed. The mesoporous design significantly increases the specific surface area, provides more active sites for the adsorption of biomolecules, and improves the detection sensitivity. When preparing the Ag / AgCl reference electrode, the Ag electrode is first immersed in a mixed solution containing 250mM silver nitrate, 750mM sodium thiosulfate, and 500mM sodium bisulfite, and then electrodeposited at a current of -0.2mA for 100 seconds. Then, 10μL of 10% FeCl3 solution is drop-cast for oxidation treatment for 1 minute. This process does not require the high temperature environment and complex precursors of chemical vapor deposition. The porous graphene is directly formed by inducing PI carbonization through laser energy, which improves material utilization and supports roll-to-roll mass production. The production capacity is greatly improved compared with the micromechanical exfoliation method. The mesoporous structure makes the specific surface area reach 1200m 2 / g, providing abundant active sites for antibody immobilization.

[0022] 10 μL of 5.0 mM 1-pyrenebutyric acid (PBA) DMF solution was drop-cast on the electrode surface and incubated for 2 hours in a room temperature and humidity controlled environment (RH50%). The electrode was then rinsed with DMF, isopropanol, and deionized water in sequence. PBA was covalently bound to the graphene surface through π-π stacking to avoid destroying the graphene conjugated structure. At the same time, carboxyl functional groups were introduced for antibody fixation. The electrode was then immersed in 0.025 M containing 0.4 M EDC and 0.1 M sulfo-NHS. The cells were activated with MES buffer (pH 6.5) for 35 minutes, and 5 μL of 250 μg / mL mouse anti-SARS-CoV-2 nucleocapsid protein (NP) monoclonal antibody, rabbit anti-S1-IgG antibody, goat anti-S1-IgM antibody, and rabbit anti-C-reactive protein (CRP) monoclonal antibody were drop-casted and incubated at room temperature for 3 hours. EDC / sulfo-NHS was used to activate the carboxyl groups, promote the directional fixation of the antibodies through amide bonds, and maintain the active conformation of the antibodies. Finally, the cells were blocked with 2.0% bovine serum albumin (BSA) in 0.01 M PBS for 90 minutes. BSA blocked unreacted sites, reduced nonspecific adsorption, reduced background signal interference, and improved detection specificity.

[0023] 2 mL of venous blood was collected from the patient in a vacuum blood collection tube containing EDTA. 20 μL of blood was diluted 100-fold to 2 mL with 0.01 M PBS (pH 7.4) containing 1.0% BSA and 0.05% sodium azide. 10 μL of the diluted sample was added dropwise to the surface of the functionalized electrode and incubated at 37°C for 10 minutes. The sample was washed three times with PBS. EDTA anticoagulant prevented blood coagulation, BSA maintained protein stability, and sodium azide inhibited microbial reproduction. Incubation at 37°C simulated physiological temperature, accelerated antigen-antibody binding kinetics, and shortened reaction time.

[0024] Add 250-fold diluted HRP-labeled detection antibody (HRP-labeled rabbit anti-NP polyclonal antibody for NP detection, HRP-labeled goat anti-CRP polyclonal antibody for CRP detection), incubate for 5 minutes, and after washing, add 1.0 mg / mL HRP-goat anti-rabbit IgG antibody for NP detection and incubate for 5 minutes. The HRP-labeled antibody forms a signal amplification system through antigen-antibody specific binding, and the enzyme catalyzes the substrate to generate an electrochemical signal. The double antibody sandwich strategy (NP detection) further improves the detection sensitivity and reduces the detection limit to 500 pg / mL.

[0025] Electrochemical detection was performed on a CHI820 electrochemical workstation. The three-electrode system was placed in 0.05 M sodium phosphate buffer (pH 6.0) containing 2.0 mM hydroquinone (HQ). After the addition of 1.0 mM H2O2, the signal was collected by chronoamperometry at a potential of -0.2 V (vs Ag / AgCl) with a sampling rate of 10 kHz. Hydroquinone served as an electron mediator to accelerate the electron transfer of H2O2 catalyzed by HRP, generating a quantifiable current signal on the electrode surface. The pH 6.0 buffer optimized enzyme activity and ensured signal stability. The high sampling rate ensured the accurate capture of the current signal, providing a data basis for quantitative analysis.

[0026] The STM32L432KC microcontroller built into the test box synchronously collects four-channel current data through a 4-channel 16-bit ADC, and transmits it to the hospital information system (HIS) via the SPBT3.0DP2 Bluetooth 5.0 module using the BLE protocol. Multi-channel synchronous acquisition enables parallel detection of NP, IgG, IgM, and CRP, shortening the overall detection time. Bluetooth transmission technology supports real-time data upload, making it easier for clinicians to quickly obtain test results and optimize triage efficiency.

[0027] This protocol enables quantitative analysis of NP (detection limit 500 pg / mL, linear range 0-6000 pg / mL), S1-IgG / IgM (detection limit 250 ng / mL) and CRP (detection limit 50 ng / mL). Testing of 10 RT-PCR-confirmed positive serum samples showed that the positive detection rates of NP, S1-IgM and CRP were 92%, 88% and 95%, respectively, with a correlation with the ELISA method of r=0.955; the intra-batch repeatability coefficient of variation CV was <8.5%, and the entire test took 15 minutes.

[0028] Example 2 The sensor was fabricated on a 125 μm polyimide substrate using CO2 laser engraving technology. The engraving parameters were power 8.0%, speed 15%, and resolution 1000 dpi. Four 2 mm × 3 mm mesoporous graphene working electrodes (specific surface area 1200 m 2 / g), a 1mm inner diameter annular Ag / AgCl reference electrode and a 5mm×5mm graphene counter electrode. The mesoporous graphene electrode is formed into a porous structure by laser engraving, which increases the specific surface area and improves the adsorption efficiency of biomolecules, laying the foundation for high-sensitivity detection. This process does not require the high temperature environment and complex precursors of chemical vapor deposition. It directly uses laser energy to induce PI carbonization to form porous graphene, which improves material utilization and supports roll-to-roll batch production. The production capacity is greatly improved compared with the micromechanical exfoliation method, and the mesoporous structure makes the specific surface area reach 1200m 2 / g, providing abundant active sites for antibody immobilization.

[0029] The electrode surface was functionalized with 5.0 mM 1-pyrenebutyric acid (PBA) in DMF for π-π stacking. After activation with 0.4 M EDC and 0.1 M sulfo-NHS, 250 μg / mL of SARS-CoV-2 spike protein (S1), NP antigen, and rabbit anti-CRP monoclonal antibody were immobilized. Finally, unreacted sites were blocked with 2.0% bovine serum albumin (BSA). PBA functionalization avoided destroying the graphene conjugated structure and introduced carboxyl groups for antigen / antibody immobilization. EDC / sulfo-NHS activation ensured directional coupling of antigen / antibody and maintained biological activity. BSA blocking reduced nonspecific adsorption and reduced background signal interference caused by saliva impurities in home testing.

[0030] The user collects 2 mL of saliva through a sterile funnel and immediately dilutes it to 10 mL with 0.01 M PBS (pH 7.4) containing 1.0% BSA and 0.1% Tween-20 at a ratio of 1:5. 10 μL of the dilution is then added dropwise to the surface of the functionalized electrode, incubated at room temperature for 5 minutes, and washed twice with PBS (50 μL each time). The sterile funnel is used to collect saliva to avoid exogenous contamination. Tween-20 acts as a surfactant to dissolve salivary mucin and prevent blockage of the electrode pores. The 1:5 dilution reduces interference from the saliva matrix. Incubation at room temperature simplifies the operating process and is suitable for non-temperature-controlled environments at home.

[0031] Add 2.0 mg / mL of HRP-labeled anti-human IgG / IgM antibody and HRP-labeled goat anti-CRP polyclonal antibody, incubate at room temperature for 5 minutes, wash with PBS, and then add 100 μL of 0.05 M sodium phosphate buffer (pH 6.0) containing 2.0 mM hydroquinone (HQ). Then add 1.0 mM H2O2 to start the reaction. The HRP-labeled antibody forms a specific bond with the antibody / CRP in the sample, and the enzyme catalytic system realizes signal amplification, generating a detectable current without the need for specialized instruments. Hydroquinone acts as an electron mediator to accelerate electrochemical signal conduction, and the pH 6.0 buffer optimizes enzyme activity to ensure the stability of home testing.

[0032] The STM32L432KC microcontroller built into the detection box collects current signals through a 4-channel 16-bit ADC at a 10kHz sampling rate. After being amplified by the AD8608 operational amplifier, the current signals are transmitted to the mobile phone APP via the BLE protocol by the SPBT3.0DP2 Bluetooth 5.0 module (transmission distance 10 meters). The high sampling rate ADC ensures accurate capture of current signals. The Bluetooth 5.0 low-power transmission is adapted to smartphones. The 10-meter transmission distance meets the requirements for use in home environments. The integrated operational amplifier enhances the weak signal detection capability to meet the needs of convenient data interaction in home scenarios.

[0033] The mobile phone APP has a built-in calibration curve (NP: I=0.12 [NP]+15.6, R 2 =0.992; CRP: I=22.5 [CRP]+85.3, R 2 =0.987), automatically calculates concentration and generates a visual report. The test data is encrypted and uploaded to the community medical cloud platform. The calibration curve is embedded in the app to achieve one-click quantitative analysis, and the results can be interpreted without professional knowledge. The visual report shows NP, antibody, and CRP levels in the form of charts, which is easy for home users to understand. Encrypted cloud storage supports remote monitoring by community doctors, realizing the interconnection between home testing and medical systems.

[0034] This solution realizes the quantitative detection of NP (detection limit 500pg / mL), S1-IgG / IgM (250ng / mL) and CRP (50ng / mL) in saliva. The sample processing time is less than 2 minutes and the total detection cycle is 10 minutes. The detection of 5 RT-PCR-confirmed positive saliva samples showed that the positive detection rates of NP, S1-IgM and CRP were 88%, 84% and 92%, respectively, and the correlation with the serum test results was r=0.912. Through integrated portable design and non-invasive saliva testing, professional medical testing technology is transformed into a home-use tool. The rapid response time of 10 minutes meets the high-frequency self-monitoring needs, providing a cost-effective solution for family screening and rehabilitation monitoring in prevention and control.

[0035] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A laser-induced graphene immunoassay rapid and low-cost remote medical detection platform, characterized in that: The platform includes the following components: Sensor array module: A patterned structure containing four graphene working electrodes, one Ag / AgCl reference electrode, and one graphene counter electrode was formed on a polyimide substrate using CO2 laser engraving technology. The structure was functionalized with 1-pyrenebutyric acid, then immobilized with specific antibodies and blocked with bovine serum albumin. Electrochemical detection module: Based on differential pulse voltammetry and electrochemical impedance spectroscopy, a double sandwich and indirect immunoassay strategy is used. After incubation of diluted blood or saliva samples, enzyme-labeled antibodies are bound and electrochemical signals are collected in a buffer containing hydroquinone and hydrogen peroxide. Wireless transmission and electronic system module: Based on the Arm Cortex-M4 microcontroller, it integrates a Bluetooth module and signal processing circuit, is powered by a lithium-ion polymer battery, and uses firmware to control detection timing and achieve wireless data transmission; Sample processing module: Blood samples were diluted 1:100 with PBS containing 1.0% BSA, and saliva samples were diluted 1:5 with PBS, and then used directly for sensor array detection.

2. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1 is characterized in that: The sensor array module uses CO2 laser engraving technology to form a patterned structure containing four graphene working electrodes, one Ag / AgCl reference electrode and one graphene counter electrode on a polyimide substrate. The laser engraving power is 8.0%, the speed is 15%, and the dots per inch is 1000. The graphene working electrode adopts a mesoporous structure design, and a porous graphene layer is formed by laser-induced PI carbonization. The specific surface area reaches 1200m 2 / g, the Ag / AgCl reference electrode was electrodeposited in a mixed solution containing 250 mM silver nitrate, 750 mM sodium thiosulfate and 500 mM sodium bisulfite at a current of -0.2 mA for 100 seconds and then drop-casted with FeCl3 solution for 1 minute.

3. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1 is characterized in that: In the sensor array module, the electrode surface was modified with π-π stacking using a 5.0 mM 1-pyrenebutyric acid (PBA) solution in DMF. After activation with 0.4 M EDC and 0.1 M sulfo-NHS, 250 μg / mL of S1-IgG, S1-IgM, CRP antibody, or 50-fold diluted NP antibody was immobilized via amide bonds, and unreacted sites were blocked with a 2.0% bovine serum albumin solution.

4. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1, characterized in that: The electrochemical detection module is based on differential pulse voltammetry (DPV) and open circuit potential electrochemical impedance spectroscopy (EIS). It uses double sandwich and sandwich detection configurations for SARS-CoV-2 nucleocapsid protein (NP) and C-reactive protein (CRP), and indirect immunoassay for S1-IgG and S1-IgM.

5. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1, characterized in that: In the electrochemical detection module, during testing, blood samples were diluted 100-fold with PBS containing 1.0% BSA, and saliva samples were diluted 5-fold. 10 μL was then incubated with a functionalized electrode for 1-10 minutes. An HRP-labeled detection antibody was added and incubated at room temperature for 5 minutes. 1.0 mM H2O2 was added to a 0.05 M sodium phosphate buffer containing 2.0 mM hydroquinone (HQ), and the amperometric signal was recorded at a potential of -0.2 V relative to Ag / AgCl.

6. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1, characterized in that: In the electrochemical detection module, HRP-labeled detection antibodies were added, NP detection was diluted 250 times, S1-IgG and S1-IgM were 2.0 mg / mL, and NP detection required additional incubation with 1.0 mg / mL HRP-goat anti-rabbit IgG for 5 minutes.

7. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1, characterized in that: In the electrochemical detection module, the DPV detection conditions are: potential range -0.2~0.6V, pulse width 0.2s, incremental potential 4mV, amplitude 50mV; EIS reaction conditions: frequency range 0.1~10 6 Hz, amplitude 5mV.

8. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1, characterized in that: In the wireless transmission and electronic system module, the signal processing circuit is composed of a single operational amplifier AD8605 and a quad operational amplifier AD8608 to form a constant potentiostat loop to achieve current signal amplification.

9. The laser-induced graphene immune rapid and low-cost remote medical detection platform according to claim 1, characterized in that: The sample processing module: blood samples are stored in EDTA-containing blood collection tubes and diluted 1:100 with 0.01M PBS containing 1.0% BSA before testing. 0.05% sodium azide is added to the diluent. Saliva samples are collected using a sterile funnel and immediately diluted 1:5 with PBS containing 1.0% BSA after collection. 0.1% Tween-20 is added to the diluent to enhance protein solubility. All diluted samples are tested within 2 hours.

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