Investigation of use of hydrophilic/hydrophobic NADESs for selective extraction of As(III) and Sb(III) ions in vegetable samples: Air assisted liquid phase microextraction and chemometric optimization

Abstract

In this paper, a green, cost-effective sample preparation method based on air assisted liquid phase microextraction (AA-LPME) was developed for the simultaneous extraction of As(III) and Sb(III) ions from vegetable samples using hydrophilic/hydrophobic natural deep eutectic solvents (NADESs). Central composite design was used for the optimization of extraction factors including NADES volume, extraction cycle, pH, and curcumin concentration. Limits of detection for As(III) and Sb(III) were 1.5 ng L^-1 and 0.06 ng L^-1, respectively. Working ranges for As(III) and Sb(III) were 0.2-300 ng L^-1 (coefficient of determination (R² = 0.9978) and 5-400 ng L^-1 (R² = 0.9996), respectively. Relative standard deviations for As(III) and Sb(III) were 2.2-2.8% and 2.9-3.2%, respectively. Enrichment factor of the method was 184 for As(III) and 172 for Sb(III). The accuracy and precision of the AA-NADES-LPME method were investigated by intraday/interday studies and standard reference material analysis, respectively. Finally, the AA-NADES-LPME method was successfully applied to microwave digested vegetable samples using the standard addition approach and acceptable recoveries were achieved.

Keywords: Arsenic and antimony analysis; Central composite design; Liquid phase microextraction; Natural deep eutectic solvent.