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Abstract: This work presents a novel approach for simultaneous determination of butylated hydroxyanisole (BHA) and propyl gallate (PG) in a very interfering environment by combining the sensitivity of molecular fluorescence and the selectivity of the second-order calibration method. The excitation–emission fluorescence matrix data are processed by applying the second-order calibration method based on the self-weighted alternating normalized residue fitting (SWANRF) algorithm. The limits of detection (LOD) were 1.2–1.3ng/ml for BHA and 2.2–2.9ng/ml for PG. The recoveries from spiked cosmetics samples are in the ranges 95.7–103.9% for BHA and 95.9–105.7% for PG. The proposed method avoids preconcentration and elution procedures, so it considerably decreases the analytical time and the experimental expenses. Because the instrument involved in the measurement is nonsophisticated, the experiments could be carried out in routine laboratories. Then it is compared with the HPLC method in dosage of cosmetics and organic reagents, runtime, cost per analysis and LOD. [Copyright &y& Elsevier]

Abstract: In this work, with the purpose of developing an effective and inexpensive method, excitation–emission matrix fluorescence data and second-order calibration method based on the self-weighted alternating trilinear decomposition (SWATLD) algorithm were combined for simultaneous determination of 2-naphthoxyacetic acid (NOA) and 1-naphthaleneacetic acid methyl ester (NAAME) in environmental samples, i.e. soil and sewage samples. In order to investigate the prediction quality of the proposed method, different strategies, such as taking spectroscopic measurements in the presence of different matrix interferents and at different fluorescence spectrophotometers, were introduced to build calibration models and comparisons among them were done subsequently. The root-mean-square error of prediction and t-test were used to compare different SWATLD-based calibration models. The limits of detection obtained for NOA and NAAME were 0.36–0.95ngmL−1 and 1.32–2.69ngmL−1, respectively, for different models. Such a chemometrics-based protocol may possess great potential to be extended as a promising alternative for more practical applications in environment monitoring and for the design of small intelligent and field-portable analytical instruments that rely on statistical discrimination, not complete instrumental separation, of the target analytes even in the presence of unknown and uncalibrated interferences. [Copyright &y& Elsevier]