Dynamic liquid‐phase microextraction with HPLC for the determination of phoxim in water samples

A new method, which involves dynamic liquid‐phase microextraction followed by HPLC with variable wavelength detection, was developed to determine phoxim in water samples. Experimental parameters affecting the extraction efficiency, such as extraction solvent, solvent volume, sampling volume, dwell time, number of samplings, and salt concentration were investigated. Under the optimal extraction conditions, phoxim was found to yield a good linear calibration curve in the concentration range from 0.01 to 10 μg/mL. The LOD is 2 ng/mL, and RSD at the 100 ng/mL levels is 8.9%. Lake water and tap water samples were successfully analyzed using the proposed method.