Zeolite imidazolate frameworks 8 as sorbent and its application to sonication-assisted emulsification microextraction combined with vortex-assisted porous membrane-protected micro-solid-phase extraction for fast analysis of acidic drugs in environmental water samples

A novel and fast procedure, sonication-assisted emulsification microextraction combined with vortex-assisted porous membrane protected micro-solid-phase extraction (SAEME-VA-mu-SPE), was developed for the gas chromatography-mass spectrometric determination of acidic drugs from environmental water samples. One advantage of the new procedure is that any solvent immiscible with water can be used as extractant solvent of SAEME and any solid sorbent can be used for mu-SPE in the SAEME-VA-mu-SPE process. In the present work, zeolite imidazolate framework 8 (ZIF-8) was employed as extraction six-bent for mu-SPE and 1-octanol as extractant solvent for SAEME. ZIF-8 has very good thermal, chemical and water stability, which make it a suitable material for the extraction of trace analytes from aqueous samples. Under the optimized extraction conditions, the developed method exhibited low limits of detection (0.01-0.04 ng/ml), good linearity (with r(2) between 0.9965 and 0.9993) from 0.5 to 50 ng/ml and satisfactory repeatability (between 4.1% and 7.6%). In essence SAEME-VA-mu-SPE is a combination of two different and efficient miniaturized techniques. It was demonstrated to be a fast, accurate, and convenient pretreatment procedure for trace analysis of environmental water samples. (C) 2012 Elsevier B.V. All rights reserved.