Determination of phenolic compounds in water using excitation- emission fluorescence matrices coupled to multiway calibration strategies

Abstract

The development of chemometrics models from first-order to second-order, third-order, and higher-order has demonstrated numerous advantages. But it does not mean that a higher-order model is the best choice for a system under study. There is a suggestion for the selection of second- and third-order models in the determination of contaminants in the water environment. In this paper, a new multi-way calibration strategy, the introduction of a temperature dimension to construct a four-way data array, was proposed. The feasibility of the proposed analytical approach was validated by experiments, and the simultaneous identification and quantification of two target analytes were achieved. In addition, two kinds of phenolic compounds, phenol and thymol, were investigated in aqueous environment to compare the performances of two three-way calibration strategies and two four-way calibration strategies. The results show that the decomposition results (average recovery, the root-mean-square error of prediction (RMSEP) values and average relative prediction error (ARPE)) of the three-way calibration strategies based on both parallel factor analysis (PARAFAC) and alternating penalty trilinear decomposition (APTLD) were comparable to those of four-way calibration strategies based on both extended parallel factor analysis (extended-PARAFAC) and alternating penalty quadrilinear decomposition (APQLD). But four-way calibration strategy could overcome high-intensity background interference and provided more reliable results than three-way calibration strategy when the concentrations of target analytes were too low. Moreover, analytical figures of merit of these models were calculated and compared. It was found that the performance of four-way calibration strategy was superior to three-way calibration strategy. The results offer a suggestion for the choice of three-way and four-way calibration strategy for the determination of phenolic compounds in aqueous environments.