Headspace single drop and hollow fiber liquid phase microextractions for HPLC determination of phenols.

Two methods based on headspace single drop microextraction (HS-SDME) and headspace hollow fiber liquid phase microextraction (HS-HF-LPME) were developed and critically compared with HPLC-UV determination of phenols (including phenol (Ph), 2-chlorophenol (CP), 2,4-dichlorophenol (DCP) and 2,4,6-trichlorophenol (TCP)) in this paper. The significant parameters affecting the extraction efficiency of the target analytes in both extraction modes were studied and the optimal extraction conditions were established. Under the optimal conditions, the detection limits (S/N = 3) for Ph, CP, DCP and TCP obtained by HS-SDME-HPLC-UV and HS-HF-LPME-HPLC-UV were 2.1, 0.2, 0.8,1.1 ng/mL and 4.2, 0.4, 0.4, 0.4 ng/mL with enrichment factors of 15.8, 198.9, 159.7, 194.8 and 9.2, 149.9, 301.9, 411.1, respectively. The RSDs obtained by HS-SDME-HPLC-UV and HS-HF-LPME-HPLC-UV were 3.7, 4.0, 9.8, 6.7% and 6.3, 3.6, 3.1, 4.8% for Ph, CP, DCP and TCP, respectively. Both extraction modes have a comparable analytical performance, but HS-HF-LPME was more robust than HS-SDME, while HS-SDME was simpler than HS-HF-LPME. The two headspace microextraction modes were applied for HPLC-UV determination of target phenols in water, honey and toner samples, and the determined values obtained by both techniques were in good agreement with each other.