Research On Technology Of Biosensors Based On The Analysis Of Interference Spectrum

Biosensor emerged in 1960 is a novel detection technology. It detects the information of biological organization by bio-molecules recognition element which is then converted to electricity, sound, light or other kind of signals by a variety of bio-sensors. Since it has some advantages such as wide range of applications, high sensitivity, high portability, and could scan the micro-structure of biological tissue, bio-sensors have a high practical value in biomedical field.This paper first introduces the research and development of fiber optic biosensor at home and abroad. According to the spectral analysis, principles of fiber optic biosensor are described. Based on the principle of low-coherence, an OCR system with common-path structure is designed. SLD is applied for light source. Its center wavelength is 849.5nm and full width at half-maximum width is 23.5nm. The resolution is 13.5um. Spectral detection system which consists of diffraction grating, CCD and other devices module is built to detect the interference spectral. Spectral detection module is optimized by calculating the incident angle of fiber and compensating the dispersion in order to expand the spectrum more uniform and symmetrical. Finally…calibrate the interference signal.Experiments show that the performances of detection module satisfy the theoretical design requirements. In the experiments of OCR system, single and multi-coverslip are simulated respectively, then the information of layers whose error range is less than 5um could be available through the process of signal detection and Fourier transform. In the tissue sample experiments, the extraction of signal is much more difficult because the back light from the organization is so weak. The information of sample thickness could also be detected because its SNR could reach to 13dB.