多功能食品安全综合快速现场检测仪设计

Design of multifunction food safety fast field detection equipment

目的设计一种食品安全快速检测仪,实现多功能、高通量检测与数据采集传输一体化,提高食品安全现场检测效率。方法通过分析比色法、酶联免疫法(enzyme-linked immunosorbent assay,ELISA)、胶体金试纸及相应仪器的工作原理,依据现场快速检测的实际需求,提出了基于分光光度法的单光束与多光束光路集成的仪器优化方案和一种基于图像处理技术的现场胶体金试纸自动快速检测方案。以MC9S12XS128单片机为控制核心,设计搭建了分光机构、胶体金试纸图像采集、试样容器、光电转换与信号调理电路等模块,实现了4通道和96通道ELISA的光路转换、信号采集与处理、试样载板控制、胶体金多元检测等功能。结果 ELISA检测模块光度准确度?T<1.403%,光度重复度δT<0.14%,通道间透光率差异小于0.97%;比色检测模块光度准确度?T<1.650%,光度重复度δT<0.50%;胶体金试纸自动读取模块,快检试纸的量化结果与真值的相关度r^2=0.84。结论 ELISA模块和比色法各项指标符合食品安全快速检测的应用要求,胶体金试纸自动读取模块量化结果与真值的相关度低于要求,需要继续进行算法和装置的优化。

Objective To propose an integrated rapid detection instrument with multi-function modules, high testing rate and auto-data acquisition in order to improve field detection efficiency of food safety. Methods Based on the working principle of colorimetry, enzyme-linked immunosorbent assay （ELISA）, colloidal gold strip and corresponding instruments, according to the requirements of field food safety rapid detection, an optimized integration design of single beam and multiple beam optical path strategy for spectrophotometry and an image processing based colloidal gold strip auto detection were proposed. Using MC9S12XS128 microcontroller as the control unit, the splitting mechanism, colloidal gold strip image collection, sample container, photoelectric conversion and signal conditioning circuit module were designed and built. The 4 and 96 channel ELISA optical path conversion, signal acquisition and processing, sample board control, colloidal gold trip auto detection were realized. Results The photometric detection accuracy ΔT was 〈1.403% of ELISA module and the photometric repeatability δT was 〈0.14%. The transmittance difference between channels was less than 0.97. The photometric detection accuracy ΔT was 〈1.650% of colorimetric detection module and the photometric repeatability δT was 〈0.50%. The correlation between the quantitative results from colloidal gold strip auto detection module and the true value r^2 was 0.84. Conclusion The ELISA module and colorimetry detection module meet the requirements for fast food safety detection. The correlation between the quantitative result and the true value of the colloidal gold strip auto detection module is lower than the requirement, so it is necessary to continue the optimization of algorithm and device.