藻红蛋白 (Phycoerythrin, PE)是衡量水体中藻类富营养化的一个重要指标, 可见光吸收法具有测量快速、准确、无二次污染、可实现在线和原位测量等优点。因此, 本文提出采用可见光吸收法测定水中藻红蛋白含量。以藻红蛋白标准液为研究对象, 采集 5~250 mg/L不同浓度标准液的可见光吸收光谱, 对藻红蛋白进行定性定量分析。同时, 对光谱的不同谱区预处理后, 运用偏最小二乘法 (PLS)建立可见光吸收光谱下的藻红蛋白校正分析模型, 并与主成分回归法 (PCR)进行比较。实验结果表明, 采用 PLS算法在谱区 480~570 nm建立的校正分析模型的相关系数 R2可达 0.993, 校正标准差 RMSEC与相对标准差 RSD最小, 分别为 5.578 3和 3.92%。

Phycoerythrin (PE) is an important indicator which measures the algae eutrophication in water. Visible absorption spectrometry has some advantages, such as rapid detection, accurate, no secondary pollution, on-line and in-situ measurements etc. Therefore, the method of detection phycoerythrin contents by visible absorption spectrometry is proposed. Based on the standard solution of phycoerythrin as experimental subjects, the visible absorption spectrometry of the standard solution are collected in the range of 5 ~ 250 mg/L, and the correction analysis model is made. The spectral preprocessing is performed in different spectral region and the Partial Least Squares (PLS) algorithm is used to establish the correction analysis model. Compared with Principal Component Regression (PCR) algorithm, the results show that the correction analysis model has the highest correlation and smallest error by the PLS algorithm made in the spectral region of 480~570 nm. The correlation coefficient root mean square error of calibration and relative standard deviation is 0.9930, 5.5783 and 3.92%, respectively.