Extraction and determination of organosulfur compounds in water samples by using homogeneous liquid-liquid micro-extraction via flotation assistance-gas chromatography-flame ionization detection

Abstract

A new method was developed for the preconcentration and determination of organosulfur compounds (OSCs) in water samples using homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA) and gas chromatography (GC) with flame ionization detection (FID). Toluene at microliter volume level and acetone were used as an extraction and a homogeneous solvent, respectively. In this research, a special extraction cell was designed to facilitate collection of the low-density solvent extraction. No centrifugation was required in this procedure. Using air flotation, extraction solvent was collected at the conical part of the designed cell. The effects of the different variables on the efficiency of the extraction such as kind and the volume of extraction and homogeneous solvents, ionic strength and extraction time were studied and optimized. Under the optimum conditions, linearity of the method were in the range from 0.25 to 200 µg L^-1 with limit of detections (LODs) (S/N = 3) were in the range from 0.05 to 0.4 µg L^-1. HLLME-FA is a fast, simple and efficient method for the determination of organic sulfur compounds in aquatic samples.

KEY WORDS: Homogeneous liquid-liquid microextraction, Flotation assistance, Organosulfur compounds, Gas chromatography, Water samples

Bull. Chem. Soc. Ethiop. 2014, 28(2), 195-204

DOI: http://dx.doi.org/10.4314/bcse.v28i2.4