Supramolecular nano solvent-based hollow fiber liquid phase microextraction as a novel method for coextraction of acidic, basic and amphiprotic pollutants

The coextraction of acidic, basic and amphiprotic pollutants from various matrixes is a considerable and disputable concept in sample preparation strategies. In this study, for the first time, coextraction of acidic, basic and amphiprotic pollutants was performed using supramolecular nano solvent-based hollow fiber liquid phase microextraction (SS-HF-LPME) as an efficient method followed by high performance liquid chromatography-photo diode array detection. The supramolecular solvent (SUPRAS) is formed from the coacervation of decanoic acid aqueous vesicles in the presence of tetrabutylammonium hydroxide. The results showed 40% SUPRAS in 1-decanol has the best extraction efficiency for three selected model analytes (4-nitrophenol, 3-nitroaniline and 1-amino-2-naphthol). The extraction process was accomplished in two phase mode and the unique interactions between the solvent and polar analytes (hydrophobic, electrostatic, hydrogen bonding and π-cation interactions) resulted in elevated coextraction efficiency. Central composite design methodology combined with desirability function approach was applied to develop predictive models for simulation and optimization of SS-HF-LPME method. The opted conditions were: pH of the sample, 9.0; percentage of SUPRAS in 1-decanol, 40%; extraction time, 30 min; salt concentration, 20% w/w; stirring rate, 1250 rpm. Under the optimum conditions detection limits and linear dynamic ranges were achieved in the range of 0.1-0.2 μg L-1 and 0.5-400 μg L-1, respectively. The percent of extraction recovery and relative standard deviations (n = 5) were in the range of 56.1-71.1 and 4.1-6.9, respectively. Finally, the applicability of this method was successfully confirmed by analyzing rain, snow and river water samples and satisfactorily.

کلیدواژه ها:

Supramolecular nano solvent ، Hollow fiber liquid phase microextraction ، Coextraction ، Central composite design ، Desirability function ، Pollutants