Determination of Chlorophenoxy Acid Herbicides in Water Samples by Suspended Liquid-Phase Microextraction–Liquid Chromatography

摘要

In this study, directly suspended liquid-phase microextraction was investigated for the extraction and determination of five chlorophenoxy acid herbicides in water samples. The optimized parameters for extraction of chlorophenoxy acid herbicides were 1 M HCl concentration in sample solution, solution temperature 20 °C, 45-min extraction time, 1,000 rpm stirring rate, 25 μL extracting solvent volume and without NaCl addition. Under the optimum conditions, the enrichment factor ranged from 192 to 390. Calibration curves yielded good linearity (R 2 > 0.999) and the linear range was 5.0–500.0 μg L−1, limit of detection was 0.3–0.4 μg L−1 and limit of quantification was 1–2 μg L−1 for analytes and the relative standard deviations were in the range of 3–10% (n = 3). Finally, the proposed method was successfully applied to the quantification of five chlorophenoxy acid herbicides in water samples and recovery was in the range of 74–110%.