Rapid Determination of Benzene Derivatives in Water Samples by Trace Volume Solvent DLLME prior to GC-FID

Abstract

An inexpensive, simple and environmentally friendly method based on dispersive liquid liquid microextraction (DLLME) for rapid determination of benzene derivatives in water samples was proposed. A significant improvement of DLLME procedure was achieved. Trace volume ethyl acetate (60 lL) was exploited as dispersion solvent instead of common ones such as methanol and acetone, the volume of which was more than 0.5 mL, and the organic solvent required in DLLME was reduced to a great extent. Only 83-lL organic solvent was consumed in the whole analytic process and the preconcentration procedure was less than 10 min. The advantageous approach coupled with gas chromatograph-flame ionization detector was proposed for the rapid determination of benzene, toluene, ethylbenzene and xylene isomers in water samples. Results showed that the proposed approach was an efficient method for rapid determination of benzene derivatives in aqueous samples.

Determination of phthalate esters in bottled water using dispersive liquid–liquid microextraction coupled with GC–MS

“…The criteria for a good extraction solvent are: (i) density higher or lower than water, (ii) low solubility in water, (iii) high capability for extraction of the analytes of interest from aqueous phase, (iv) it should be easily dispersed through dispersive step and (v) good chromatography behavior . The main criterion for the selection of disperser solvent are: (i) miscibility in both the phases (extraction solvent and the aqueous sample) , (ii) less surface tension . Based on the above criteria; different extraction solvents (hexane, isooctane, n ‐pentane, toluene, and xylene) and dispersive solvents (methanol, acetonitrile, and acetone) were selected for method optimization.…”

“…When the volume of methanol was too low, the dispersion did not take place completely . A reduction in the EF was observed when the volume of methanol exceeded 20 μL; due to the fact that the solubility of analyte in water increases as the volume of methanol increases . Hence, 20 μL of methanol was chosen as the optimum dispersive solvent volume.…”

“…In this method, the mixture of low density/high density solvent (extraction solvent) relative to water and dispersive solvent (water‐miscible solvent) is rapidly injected by a syringe into an aqueous sample. A cloudy solution consisting of very fine droplet of extraction into aqueous phase is formed . The advantages of this pretreatment technique are rapidity, simplicity, low cost, low solvent use, short extraction time, and high recovery and enrichment factors .…”

Analysis of Losartan And Carvedilol in Urine And Plasma Samples Using A Dispersive Liquid–Liquid Microextraction Isocratic Hplc–Uv Method

“…A ternary solvent extraction system, including dispersive solvent, extraction solvent and aqueous samples containing target analyte, provides a simple, rapid and cheap method that leads to a high enrichment factor and high recovery. DLLME has been widely applied for environmental and food samples [9][10][11][12][13][14][15][16][17][18][19], while its application for drug ana lysis in biological matrices has been rarely studied (Table 2) . Urine was studied as the most common biological sample, and plasma, serum, whole blood and saliva were analyzed for the applicability of DLLME for drug extraction from biological samples.…”

In-syringe reversed dispersive liquid–liquid microextraction coupled to high performance liquid chromatography for the determination of sulfonylurea herbicide residues in cereal samples

“…The following characteristics should be considered for the disperser solvent: (i) high water solubility but not miscible in water, (ii) miscible in the extraction solvent, and (iii) small surface tension. 45 In addition, the physical and chemical characteristics of analytes need to be taken into consideration. In this study, the commonly used disperser solvents, including ethyl acetate, acetonitrile, and methanol, were studied.…”