Kumar Keshav
Institute for Wine analysis and Beverage Research, Hochschule Geisenheim University, 65366, Geisenheim, Germany.
J Fluoresc. 2018 Mar;28(2):589-596. doi: 10.1007/s10895-018-2221-8. Epub 2018 Mar 29.
Excitation-emission matrix fluorescence (EEMF) and total synchronous fluorescence spectroscopy (TSFS) are the 2 fluorescence techniques that are commonly used for the analysis of multifluorophoric mixtures. These 2 fluorescence techniques are conceptually different and provide certain advantages over each other. The manual analysis of such highly correlated large volume of EEMF and TSFS towards developing a calibration model is difficult. Partial least square (PLS) analysis can analyze the large volume of EEMF and TSFS data sets by finding important factors that maximize the correlation between the spectral and concentration information for each fluorophore. However, often the application of PLS analysis on entire data sets does not provide a robust calibration model and requires application of suitable pre-processing step. The present work evaluates the application of genetic algorithm (GA) analysis prior to PLS analysis on EEMF and TSFS data sets towards improving the precision and accuracy of the calibration model. The GA algorithm essentially combines the advantages provided by stochastic methods with those provided by deterministic approaches and can find the set of EEMF and TSFS variables that perfectly correlate well with the concentration of each of the fluorophores present in the multifluorophoric mixtures. The utility of the GA assisted PLS analysis is successfully validated using (i) EEMF data sets acquired for dilute aqueous mixture of four biomolecules and (ii) TSFS data sets acquired for dilute aqueous mixtures of four carcinogenic polycyclic aromatic hydrocarbons (PAHs) mixtures. In the present work, it is shown that by using the GA it is possible to significantly improve the accuracy and precision of the PLS calibration model developed for both EEMF and TSFS data set. Hence, GA must be considered as a useful pre-processing technique while developing an EEMF and TSFS calibration model.
激发-发射矩阵荧光(EEMF)和全同步荧光光谱(TSFS)是常用于分析多荧光团混合物的两种荧光技术。这两种荧光技术在概念上有所不同,且各有一定优势。对如此大量高度相关的EEMF和TSFS进行人工分析以建立校准模型很困难。偏最小二乘法(PLS)分析可以通过找出使每个荧光团的光谱信息与浓度信息之间的相关性最大化的重要因素,来分析大量的EEMF和TSFS数据集。然而,通常对整个数据集应用PLS分析并不能提供稳健的校准模型,需要应用合适的预处理步骤。本研究评估了在对EEMF和TSFS数据集进行PLS分析之前应用遗传算法(GA)分析,以提高校准模型的精度和准确性。GA算法本质上结合了随机方法和确定性方法的优势,能够找到与多荧光团混合物中每个荧光团浓度完美相关的EEMF和TSFS变量集。使用(i)四种生物分子稀水溶液混合物的EEMF数据集和(ii)四种致癌多环芳烃(PAH)混合物稀水溶液的TSFS数据集,成功验证了GA辅助PLS分析的实用性。在本研究中,结果表明,通过使用GA,可以显著提高为EEMF和TSFS数据集开发的PLS校准模型的准确性和精度。因此,在建立EEMF和TSFS校准模型时,GA必须被视为一种有用的预处理技术。