基于二阶校正法的多环芳烃污染物荧光检测

Fluorescence detection of polycyclic aromatic hydrocarbon pollutants based on second-order calibration methods

为了对复杂体系的多环芳烃进行定性识别和定量分析,构建了基于二阶校正法的荧光检测系统。利用二阶校正法在三维荧光数据处理中的优势,达到多种混合多环芳烃分离和鉴别的目的。采用FS920荧光光谱仪测量并分析了萘(NAP)、苊(ANA)及两者混合物的荧光光谱特性,发现NAP溶液有一个荧光峰λex/λem=290/322nm,ANA溶液存在两个荧光峰分别为λex/λem=290/322nm和λex/λem=290/336nm,NAP和ANA荧光光谱重叠严重,并且不同浓度配比混合物的荧光光谱具有差异性。通过将二阶校正法与三维荧光光谱法相结合,实现对多环芳烃混合物的浓度检测。分别采用平行因子(PARAFAC)算法和自加权交替三线性分解(SWATLD)算法对光谱数据进行分解。结果表明:两种算法对NAP和ANA混合物均有较高的分辨能力,预测平均回收率均在95%~99%、均方根误差均小于0.2μg/L。相比之下,SWATLD算法的检测效果更好。

In order to achieve qualitative identification and quantitative analysis of complex systems of Polycyclic Aromatic Hydrocarbons(PAHs),fluorescence detection based on second-order calibration methods was proposed.The spectral data of complex systems of PAHs were identified and decomposed by exploiting second-order calibration methods to analyze three-dimensional fluorescence data.The fluorescence spectra of acenaphthene(ANA),naphthalene(NAP),and their mixture were obtained using a FS920 steady-state fluorescence spectrometer.Analysis of their fluorescence spectra revealed a characteristic fluorescence peak of NAP atλex/λem=290/322 nm and the existence of two characteristic fluorescence peaks for ANA atλex/λem=290/322 nm andλex/λem=290/336 nm.The results indicate that the fluorescence spectra of ANA and NAP overlap significantly.Moreover,when the concentration ratios are different,the fluorescence characteristics of the mixture are different.Second-order calibration methods combined with three-dimensional fluorescence spectroscopy was applied to precisely detect the concentration of the solution.Parallel factor analysis(PARAFAC)and self-weighted alternating trilinear decomposition(SWATLD)were adopted to decompose the spectral data.The experimental results show that both algorithms exhibit a high resolution for the mixture of NAP and ANA,and the average recovery rate is between 95%and 99%with a root mean square error less than 0.2μg/L.However,the SWATLD algorithm shows a better detection result.