| Magnetoelastic(ME)sensor is a new detection technology based on ME sensing technology.After years of development,the ME sensor is a passive wireless biosensor,and its research and application cover many fields such as non-destructive testing,biological detection,environmental monitoring and food safety.Compared with traditional sensors,it has the advantages of high sensitivity,passive wireless measurement,low cost and rapid detection,especially in the field of biomedical testing,which has a broad development trend and application prospect.Firstly,this paper investigates the basic principles of ME sensors and the development status of detection devices at home and abroad,and discusses and analyzes three methods of detecting resonance frequency.Based on the impedance measurement method,through the design of the hardware circuit and the design of the software algorithm,a portable system for detection of resonance frequency for ME sensor based on STM32 was optimized.In terms of circuits,design temperature sensor detection integrated circuits;software aspects optimize the detection algorithm,increase the data storage function,and control the temperature by writing algorithms.The temperature can be detected in real time so that the antigen and antibody are at the most suitable temperature to ensure the optimal binding of the antigen and the antibody modified on the surface of the ME sensor.After the collected data is optimized by software and hardware,the obtained data is more accurate,making the waveform smoother,and reducing the impact caused by accidental impulsive interference.By optimizing the data storage,after the data is analyzed and calculated,the concentration of the solution to be calculated can be calculated from the offset of the detected resonance frequency,and it can be displayed on the LCD screen to convert the instrument from qualitative to quantitative.The measurement accuracy and reliability of the measurement system were experimentally measured;the results show that the system can be used to measure the resonance frequency of the ME sensor.Secondly,the portable system was designed to detect the level of CSFV E2 antibody in pig serum solution to determine the vaccination status.ELISA kit and Receiver operating characteristic(ROC)curve were used to calibrate the portable device for detecting classical swine fever virus(CSFV)E2 antibody.The results show that the portable device has an excellent match with those from ELISA kit measurements and the accuracy rate was 98.33%,which is capable of quickly and specifically measuring CSFV E2 antibody.It has the good specificity and stability.Furthermore,the proposed device possesses the ability for diagnosing of CSF and effective monitoring of vaccination in CSF eradication.Finally,the application of portable ME sensor detection system is studied.A portable ME sensor detection system was used to detect human serum albumin(HSA)rapidly,economically and efficiently with a small sample size of microliter.The performance of the portable device was validated to be comparable to that of the Vector Network Analyzer(VNA)AV3620 using different concentrations of HSA solution.The RFS were linearly proportional to the HSA concentrations in the range from 0.1 to 100 ?g/m L with a linearity up to 0.998,a sensitivity of 8.70 Hz/?g.m L-1 and a detection limit of 0.039 ?g/m L,indicating good feasibility of this method.Meanwhile,the response of this portable ME biosensor was quick and specific to HSA targets.This ME biosensor shows high potential to be used in diagnosing abnormal HSA. |
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