The Development Of Blood Type Analyzer Based On Biological Impedance Technology

Blood typing has great significance in clinical medicine. The speed and accuracy ofidentification is an important indicator in evaluation methods for identification. Currently,there are many methods, such as hemagglutination test, cassette, MGT, flow cytometry,ELISA and so on. However, with the accelerated process of industrialization, people wantrapid and accurate detection methods, the application of innovation and new technologyprovides new methods for blood typing to faster and more accurate. Blood has a uniqueelectrical properties, after joining the pecific antibodies into different blood, its electricalcharacteristics will change with the settlement process. Using bioelectrical impedancetechnology wo can complete blood typing according to extract the relevant information ofblood electrical characteristics in real time.In this study, treating blood impedance characteristics as study object, with biomedicalbioimpedance theory, use LabVIEW, FPGA, the two electrodes measurements, spectrumanalysis and PNN network technology to build blood complex impedance measurementsystem to study the connection between the complex impedance characteristic and differentblood type, in order to achieve fast and accurate detection. Details are as follows:①After researching the results of previous in bio-impedance technology and analysis ofblood, we have completed the overall design of the whole system and proposed a method ofimpedance spectroscopy analysis. First, use multi-frequency technology to measure bloodimpedance spectroscopy (amplitude and phase), then select the PNN network modelanalytical processing the agglutination level of samples to determine blood types.②According blood detection index based on blood electrical impedance characteristics,established blood impedance detection system based on LabVIEW and FPGA. Have finishedthe signal generating circuit based on AD9850chip designing, the constant conversion circuitbased on OPA637, the design of measuring tank, the differential amplification circuit basedon OP37.③The papercompleted the communication and software design of the system, includingthe design of control program of lower machine, serial communication, data collection, dataprocessing and preservation and data acquisition mode.④Key parts of the bioelectrical impedance measurement system was constructed andtested. AD9850excitation signal source meet the performance requirements at40~5kHz, which is the system required. The output current and input voltage of constant current sourceare linear correlation, whose ratio CV is2.02%. Finally,we chose213platinum electrodes asmeasuring and the electrode spacing is3cm. The paper corrected the amplitude and phasemeasured values. The performance of the entire system was tested. The amplitude relativeerror average is2.74%. The average of absolute error is0.55°. After these, we finished theblood hemagglutination level identification test, only one misjudgment, preliminary verifythe feasibility of the system in blood hemagglutination level identification.