Full evaporation headspace single-drop microextraction (FE-HS-SDME) in combination with air-agitated liquid−liquid microextraction based on the solidification of a floating organic droplet (AALLME-SFO) was developed as an effective preconcentration technique. Chlorobenzenes were used as model analytes to evaluate the performance of the method. In the AALLME-SFO step, cyclohexane was used as the extraction solvent. Moreover, hexadecane was used for extracting analytes in the FE-HS-SDME step. The analytes were extracted from water samples and then quantified by gas chromatography coupled with electron-capture detection. Experimental factors influencing FE-HS-SDME and AALLME-SFO were evaluated. Based on the findings, limits of detection in the range of 0.003–0.006 µg/L were obtained. The technique showed good precision with a relative standard deviation of less than 7%. Excellent linearity (R2 > 0.9993) was achieved between 0.01 and 3.00 µg/L. The method demonstrated high sensitivity with acceptable recoveries between 80 and 100% for the extraction of analytes from wastewater samples.
Saraji et al. (Fri,) studied this question.