基于矩阵模型进行抗荧光干扰的蓝藻原位检测方法

摘要

藻蓝蛋白与叶绿素a作为特征色素常用于表征蓝藻的生物量.藻蓝蛋白与叶绿素a通常用荧光光谱或原位荧光强度检测,但是在实际水体中藻蓝蛋白与叶绿素a的荧光效应相互干扰会影响测量精度,极大限制了该方法的应用.本文根据朗伯比尔定律,利用二阶矩阵模型设计了一套在荧光检测过程中"激发光-发射光"优化抗干扰的波长选择方法,并利用多元线性回归分析建立了两种色素浓度与荧光强度之间的多元校正线性模型,实验验证了所筛选蓝藻荧光分析法中特定激发光和发射光波长的有效性.本研究实现了两种色素检测过程中的成功解耦,可在藻蓝蛋白的原位检测中排除水体中藻蓝蛋白与叶绿素a之间的相互干扰,提高藻蓝蛋白和叶绿素a的原位检测精度,为开发便携式蓝藻检测传感器时的波长选择提供理论基础.%Phycocyanin and chlorophyll-a are characterizations of cyanobacterial biomass.These two pigments are detected in situ with fluorescence spectrum method or fluorescence intensity.However,due to the fluorescence interference between phycocyanin and chlorophyll-a,the accuracy of in-situ detection of cyanobacteria is relatively low,which limited the application of this method.In this study,we developed a novel method of fluorescence analysis based on a two-order matrix model and a multivariate calibration linear model for the correlation between the fluorescence intensity and pigment concentration,which was verified by experiment.The established method decoupled the two mixed pigments as well as quantitatively analyzed the wavelength selection of excitation and emission and largely eliminated the fluorescence interference between phycocyanin and chlorophyll-a,and therefore,significantly improved the accuracy of in-situ detection of cyanobacteria.More importantly,our study can provide theoretical basis for the cyanobacteria detection sensor in how to select wavelengths.