Vortex-assisted binary solvent dispersive liquid–liquid microextraction for the determination of two 4-alkylphenols and Bisphenol A in drinking water by HPLC-DAD

• A green VA-BS-DLLME method was developed for BPA and alkylphenols in water. • Optimized conditions achieved low LODs (0.08–0.21 μg L −1 ) and high enrichment factors. • Spike recoveries (91.8–104.7%) ensure accuracy and compliance with EU regulations. This work proposes a green and simple method for the determination of trace levels of Bisphenol A and two alkylphenols (4- tert -octylphenol (4-tOP) and 4- tert -butylphenol (4-tBP)) in water intended for human consumption. The method consisted of using vortex-assisted binary solvent dispersive liquid–liquid microextraction (VA-BS-DLLME) as a sample preparation technique, prior to analysis by high-performance liquid chromatography with a diode array detector (HPLC-DAD). The proposed method involved the combination of two microextraction techniques. The binary solvent technique significantly improved the extraction efficiency, while the vortex assistance was used to promote the dispersion of the solvent-sample mixture. A comprehensive multivariate experimental design was carried out to determine the optimal microextraction conditions. The optimal conditions were as follows: binary extraction solvent (100 µL 1-octanol and hexane, 20:80), 3 mL of acetone, and 4 min of vortex agitation. Under the optimum conditions, limits of detection (LOD) between 0.08, 0.13, and 0.21 μg L -1 were found for BPA, 4-tBP, and 4-tOP, respectively. The intra- and inter-day precision (expressed as relative standard deviation − RSD) were less than 7.3 % and enrichment factors ranged from 32 to 74. Spike recovery experiments were carried out on tap water, well water, and bottled water samples, obtaining relative recoveries between 91.8 % and 104.7 %. The results of the proposed method demonstrate that a rapid and sensitive analysis of the target analytes in water samples can be performed, facilitating compliance with regulatory requirements (EU Directive 2020/2184) for the safety and health of drinking water.