Salicylic acid determination in estuarine and riverine waters using hollow fiber liquid-phase microextraction and capillary zone electrophoresis.

A low-cost methodology using hollow fiber liquid-phase microextraction (HF-LPME) and capillary zone electrophoresis (CZE) with UV-Vis detector was developed to analyze the salicylic acid (SA) in estuarine and riverine waters. The technique is easy-to-use and rapid, and demands little volume of organic solvent. The extraction was carried out using a polypropylene membrane supporting into octan-1-ol. HF-LPME under optimized conditions (donor solution sample pH 2, acceptor solution pH 14, sample volume 25 mL, fiber length 10 cm, acceptor volume 25 μL, extraction time 3 h and stirring speed 350 rpm) presented high enrichment factor (407 times) and good recovery in real water samples (from 88 to 110%). A limit of detection of 2.6 μg L-1 was achieved using CZE with UV-Vis detector as quantification method. The method was applied to direct quantification of SA in environmental complex estuarine and riverine water matrices.