Homogeneous liquid-phase microextraction followed by filtration-based phase separation coupled to high-performance liquid chromatography

Abstract

A simple homogenous liquid-phase microextraction methodology applying octanoic acid as the extraction phase was introduced for determination of chlorobenzenes. In this approach, phase separation phenomenon occurred by changing pH of the solution. The extraction phase was isolated based on filtration of emulsion instead of centrifugation and it was introduced to the high-performance liquid chromatography instrument as an on-line procedure. This method was used for extraction and determination of five chlorobenzenes in different samples. Experimental design and response surface methodology were used for the optimization of various parameters influencing the extraction efficiency of the method. Under optimal conditions, chlorobenzenes were effectively extracted, and preconcentration factors of 255-294 were obtained. The calibration curves were investigated in the concentration range of 1-200 μg/L and good linearity was achieved with coefficient of determinations better than 0.997. Limits of detection of 0.1 and 0.3 μg/L and suitable precision with relative standard deviations better than 5.1% (n = 5) were attained. Finally, the proposed method was applied to determine the concentration of chlorobenzenes in different samples and acceptable recoveries were gained.

Simple determination of some antidementia drugs in wastewater and human plasma samples by tandem dispersive liquid–liquid microextraction followed by high‐performance liquid chromatography

“…On the other hand, DLLME provides a high enrichment and recovery in a very short period of time. Since its invention in 2006 , continually growing studies have focused on the DLLME extraction method due to its remarkable virtues . In this method, a microvolume of the extracting solvent is dispersed into the sample solution, which increases the surface area between the acceptor and donor phases, and this phenomenon facilitates and accelerates the mass transfer of the analytes to the organic solvent.…”