Diminishing of the Electroendosmosis Flow in Gel Electromembrane Extraction for Quantification of Chromium Species in Environmental Samples

For the first time, the effect of electroendosmosis (EEO) flow phenomenon was investigated in detail, on the gel electromembrane extraction (G-EME). In this regard, various agarose-based gel membrane types with low-, medium- and high-EEO were fabricated and tested. Cr(III) and Cr(VI) were simultaneously extracted from an aqueous sample (pH ۳.۰) via the cathodic and anodic gel membranes (pH ۳.۰ for both membranes), into the cathodic and anodic aqueous acceptors (۲۰۰ μL each, pH ۲.۰), respectively. After extraction at the optimal conditions (i.e., voltage: ۳۲ V, extraction time: ۲۲ min), the both compounds were quantified by a cheap and easy-to-perform reader platform termed as microfluidic paper-based analytical device (μPAD). The results showed that high extraction recoveries referred to ۸۷% for Cr(III) and ۷۵% for Cr(VI), were acquired when the low-EEO agarose gel membrane with ۵% (w/v) dextrin was used. Also, limits of detection (LODs) of ۰.۵ and ۰.۷ ng mL-۱ for Cr(III) and Cr(VI) were obtained, respectively.

کلیدواژه ها:

Dual gel electro-membrane ، Electroendosmosis flow ، Green extraction ، Agarose.