Key Technology Research Of Fluorescence Polarization Immunoassay Analyzer

As the main equipment of immunity detection and analysis, fluorescence polarization immunoassay analyzer is urgently needed to realize domestic self-developed. It has a broad application in the prevention and control of infectious diseases, pesticide residues, food additives, environment monitoring, and other fields. The optical system as the core of the instrument is mainly composed of the lighting system, fluorescence excitation system and fluorescence detection system. This paper focused on the optical system design of fluorescence polarization immunoassay analyzer, and made the optical design and stimulation for lighting system and the key units of the optical system.First of all, this paper made a simple description of the fluorescence polarization immunoassay analyzing technology, and summarized the current research situations at both home and abroad. Then the dynamic theory of fluorescence and fluorescence polarization immunoassay technique was discussed in details, and was analyzed contrastively with the heterogeneous tag immune methods. By means of physical computing of fluorescence dynamics, the overall design of the optical system was determined.Second of all, the lighting system and units of the optical system were designed. The specific contents were as follows:1. The lighting system was designed by physical computing based on fluorescence excitation characteristics. Then it was proposed that using LED as the excitation source and establishing the equation of the relationship between the source and the target surface by geometrical optics theory to determine the parameters of the surface. And then a small-caliber, compact and high-collimation lighting distribution system was obtained. The simulation results showed that the LED as the light source of which the surface area was 1 mm × 1 mm could achieve a collimated illumination that had a divergence angle of ±2.4 °, and the system energy efficiency was up to 85%, which was an effective design for miniaturizing the fluorescence polarization immunoassay analyzer optical system.2. The optical system adopted a common optical path of the fluorescence excitation optical system and fluorescence detection optical system. The design requirements of the objective lens were determined by the analysis of the common-path optical system. A common-path objective lens of which NA = 0.4, and working distance was equal to 8 mm was designed. The structure design could increase the fluorescence collecting efficiency because of its large NA. Then a focusing lens group matching the common-path objective lens was designed as part of the fluorescence detecting optical system, which increased the fluorescence quanta entering the receiving window of PMT effectively.Finally, a complete modular structure design was introduced based on the modularization of the fluorescence polarization immunoassay analyzer optical system. And the overall optical system was simulated with optical design software, which laid conditions for the successful production of fluorescence polarization immunoassay instruments with independent intellectual property rights.