Magnetic Solvent Bar Liquid-Phase Microextraction Followed by Gas Chromatography-Flame Ionization Detection for the Trace Determination of Selected Polycyclic Aromatic Hydrocarbons in Environmental Water Samples

A novel and efficient hollow fiber-based method, viz. magnetic solvent bar liquid-phase microextrac-tion (MSB-LPME) combined with gas chromatography-flame ionization detection (GC-FID) was successfully devel-oped for the trace determination of selected polycyclic aromatic hydrocarbons (PAHs) in environmental water sam-ples. The target analytes were extracted from sample solution to the organic solvent immobilized in a fiber. After ex-traction, the analyte-adsorbed magnetic solvent bar could be readily isolated from the sample solution by a magnet which could greatly simplify the operation and also decline the total pretreatment time. The bar was first eluted with methanol, evaporated to dryness while the residue was dissolved in toluene and finally injected into GC-FID. Begin with, effective parameters controlling the performance of the microextraction were evaluated and optimized. The val-ues of the detection limit of the method were in the range of 0.05-0.08 μg L-1 and the RSD% values for the analysis of 10.0 μg L-1 of the analytes was below than 5.8% (n= 6). A good linearity (0.998 ≥ r2 ≥ 0.994) and a broad linear range (0.1-200 μg L-1) were obtained. The method was eventually utilized for the preconcentration and determination of the PAHs in environmental water samples and satisfactory results were obtained.