Bar Adsorptive Microextraction Coated with Carbon-based Phase Mixtures for Performance-Enhancement to Monitor Selected Benzotriazoles, Benzothiazoles, and Benzenesulfonamides in Environmental Water Matrices.

In the present work we propose, for the first time, bar adsorptive microextraction coated with carbon-based phase mixtures, followed by microliquid desorption and high performance liquid chromatography-diode array detection (BAμE-μLD/HPLC-DAD) analysis, to enhance the performance of the determination of traces of benzotriazoles (BTRs), benzothiazoles (BTs), and benzenesulfonamide derivatives (BSDs) in environmental water matrices. Assessing six carbon-based sorbents (CA1, CN1, B test EUR, SX PLUS, SX 1, and R) with different selectivity properties allowed us to tailor the best phase mixture (R, 12.5%/CN1, 87.5%) that has convenient porosity, texture, and surface chemistry (pH ~6.5) for trace analysis of benzenesulfonamide, 1-hydroxybenzotriazole, 1-benzotriazole, 5-methyl-1-benzotriazole, benzothiazole, and 1,3-benzothiazol-2-ol chemicals in aqueous media. Optimized experimental conditions provided average recoveries ranging from 37.9% to 59.2%, appropriate linear dynamic ranges (5.0 to 120.0 µg L; ≥ 0.9964), limits of detection between 1.0 and 1.4 μg L, and good precisions (relative standard deviation (RSD) ≤ 9.3%). The proposed methodology (BAμE(R, 12.5%/CN1, 87.5%)-μLD/HPLC-DAD) also proved to be a suitable sorption-based static microextraction alternative to monitor traces of BTRs, BTs, and BSDs in rain, waste, tap, and estuarine water samples. From the data obtained, the proposed approach showed that the BAμE technique with the addition of lab-made devices allows users to adapt the technique to use sorbents or mixtures of sorbents with the best selectivity characteristics whenever distinct classes of target analytes occur simultaneously in the same application.