Application of nonionic surfactant as a new method for the enhancement of electromembrane extraction performance for determination of basic drugs in biological samples

This paper proposes for the first time the use of a nonionic surfactant for the enhancement of electromembrane extraction performance. The presence of nonionic surfactant in donor phase promotes ionic analytes efficient migration through the organic liquid membrane. Surfactant assisted electromembrane extraction coupled with capillary electrophoresis was used for the extraction of basic drugs (methamphetamine, ephedrine and methadone) from biological samples. Parameters that affect the extraction efficiency were investigated and optimized for the proposed method. Optimal extractions were accomplished with 2-nitrophenyl octyl ether as the supported liquid membrane, with 125 V as the driving force and 0.2 mM Triton X-100 with pH 5.0 in donor and pH 1 in acceptor solutions. Equilibrium extraction conditions were obtained after 20 min of operation where the whole assembly agitated at 1000 rpm. Under the optimum experimental conditions, good limits of detection (0.90-2.42 ng mL(-1)), linearities (R-2 > 0.9995), and repeatability of extraction (RSDs below 4.4%, n = 5) were obtained. Finally, the developed method was applied to drug level monitoring in the biological samples including hair and urine samples and satisfactory results were obtained. (C) 2014 Elsevier B.V. All rights reserved.