The Study And Implementation Of The Fluorescence Immunochromatographic Quantitative Detection System Based On DSP

The immunoassay is an effective biomedical detection methods,The method of fluorescence immunoassay analysis introducing into immunoassay can improve the sensitivity and degree of accurancy of the immunoassay. The design of a the immunochromatographic detection system based on fluorescence analysis can be treated to achieve the quantitative detection of the substance,and the detection system can be applied to the food and drug detection, pathogenic bacteria drug detection and early diagnosis of myocardial infarction.Fluorescent immunochromatographic quantitative detection system mainly includes the generation of the fluorescence signal, the acquisition of fluorescence signal and the processing of the fluorescence signal. First, we designed the optical system that generate the fluorescence signal and realize the transmission path of light, then we design the photoelectric conversion system for converting the fluorescence signal to voltage signals; Secondly,we achieve the design of a signal acquisition system with the use of high-performance microprocessor and obtained signal of the characterization of the sample under test concentration; Finally, the signal was processed and analyzed to establish the relationship between the signal eigenvalues and the concentration of the sample under test curve. Therefore, the content can be divided into the following aspects:(1)To investigate the fluorescence immunochromatographic detection technology developmet, we analyzed the basic principle of the immunochromatographic detection and fluorescence quantitative analysis, and studied the fluorescence analysis applied to the immunochromatographic test quantitative detection of mathematical calculation model.(2) Based on the intruction of fluorescence quantitative detection principles and according to the excitation spectra and emission spectra of the fluorescent markers, we selected the proper light source and determined the best detection wavelength. Then we designed the optical system for optical transmission and the photodetection circuit that is responsible for the photoelectric conversion and the electric signal’s amplification, and the photoelectric detection system was tested in the end.(3) We designed the fluorescence immunochromatographic quantitative detection signal acquisition system which is based on the the TMS320F2812 DSP microprocessor. After analysis the cause of error in the ADC module and correct it, we used the ADC module to achieve the collection of the fluorescence signal.At last we designed hardware circuit,the design of interface and software of acquisition system.(4) Based on the noise characteristics of fluorescence signal, we proposed the improved threshold of spatial correlation noise reduction algorithm with wavelet transform, to remove the noise containing in fluorescence signal. Wavelet modulus maxima value transformation method is applied to recognized the edge of control strip and testing strip, and the use of peak recognition algorithm for precise identification of the peak. At last, we established quantitative detection curve, that is signal eigenvalue and the relation curve of the material concentration under test, and get the systematic detection limit and repeatability.Experiment results of fluorescence immunochromatographic quantitative detection system show that the fitting curve can effectively reflect the changes in the concentration of the standard solution, the repeatability error of the system is in less than 2%, and the detection limit can be achieved at 200ng/mL, which shows the detection system can meet the quantitative detection requirements.