A simple hollow fiber renewal liquid membrane extraction method for analysis of sulfonamides in honey samples with determination by liquid chromatography-tandem mass spectrometry

A sensitive and precise analysis using hollow fiber renewal liquid membrane (HFRLM) extraction followed by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) is described for determination of five sulfonamides in honey samples. In this procedure, the organic solvent introduced directly into the sample matrix extracts the sulfonamides and carries them over the polypropylene porous membrane. An organic solvent is immobilized inside the polypropylene porous membrane, leading to a homogeneous phase. The stripping phase at higher pH in the lumen of the membrane promotes the ionization of the target compounds releasing them to this phase. The most important parameters affecting the extraction efficiency were optimized by multivariable designs (pH and sample mass, pH and buffer for stripping phase, extraction temperature and time, type and volume of extractor solvent and use of salt to saturate the sample). Detection limits in the range of 5.1-27.4 mu g kg(-1) and linearity coefficient of correlation higher than 0.987 were obtained for the target analytes. The results obtained for the proposed method show that HFRLM-LC-MS/MS can be used for determination of the five sulfonamides studied in honey samples with excellent precision, accuracy, practicality and short analysis time. (C) 2010 Elsevier B.V. All rights reserved.