Hollow Fiber Liquid Phase Microextraction as an Advantageous Approach for Preconcentraton of Malachite Green in Environmental Water

A two-phase hollow fiber liquid phase microextraction (HF-LPME) by coupling with high performance liquid chromatography (HPLC) was developed to analyze malachite green (MG) in environmental water. In this method, 1-octyl-3-methylimidazolium hexafluorophosphate ([C8MI[PF6]) was selected as extraction agent, and several parameters (sample pH, salinity, extraction time, shaking rate, volume of donor phase) that could affect extraction performance were investigated. Under the optimal extraction conditions (sample pH, 5; salinity, 4% sodium chloride; extraction time, 6 h; shaking rate, 200 rpm; volume of donor phase, 200 mL), the established method showed excellent characters as: high enrichment factor (1193), wide linear range (0.2-100 μg L-1), low detection limit (0.1 μg L-1), good reproducibility (relative standard deviation, RSD 8.4%, n= 5) and satisfactory recovery (102.8%, n= 5). The approach was applied in real water samples analysis, which indicated that it has great potentials for rapidly monitoring low concentration of MG in environmental waters.