Investigation of directly suspended droplet micro extraction method for extraction of trihalomethane and halomethane in water samples

Simple and efficient directly suspended droplet micro extraction (DSDME) in conjunction with gas chromatography-electron capture detector (GC-ECD) has been developed for extraction and determination of Halomethane and Trihalomethane from water samples. In this technique a micro drop of n-hexane is delivered to the surface of an aqueous sample while being agitated by a stirring bar in the bulk of solution. Factors relevant to the extraction efficiency were studied and optimized. The optimized extraction conditions were extraction solvent: n- hexane; NaCl concentration: 1 M; solvent extraction volume: 50 μL; stirring rate: 720 rpm and the extraction time: 5 min. The detection limits of the method were in the range of 0.059–0.137 µg L^?1, relative standard deviation (n = 3) range were 0.019–0.048%. A good linearity (r² ≥ 0.997) and a relatively broad dynamic linear range (10–200 µg L^?1) were obtained and recoveries of method were in the range of 97.69–99.51%. Finally, the proposed method was successfully utilized for pre concentration and determination of halo methane in different real samples. Successfully DSDME technique combined with capillary GC-ECD for the analysis of THMs and HMs in the water investigated samples.