Pulsed electromembrane method for simultaneous extraction of drugs with different properties

In the current work, a new setup including two cathodes and one anode was designed and employed for the first time for pulsed electromembrane extraction (PEME) of atenolol (ATE) and betaxolol (BET) from water, urine, and plasma samples. Because these analytes have different lipophilicities, the composition of supported liquid membrane (SLM) should be optimized for each drug and it is impossible to extract them simultaneously using common electromembrane setups. The SLMs employed for the extraction of BET and ATE were pure 2-nitrophenyl octyl ether (NPOE) and a mixture of 90% NPOE and 10% di-(2-ethylhexyl) phosphate (DEHP), respectively, which were immobilized in the pores of two different hollow fibers. An electric field of 100 V was applied to transfer the analytes from the sample solution across the SLMs into acidic acceptor solutions with pH 1.0 that were located inside the lumens of hollow fibers. Pre-concentration factors in the range of 69 to 363 and satisfactory repeatabilities (2.2 < relative standard deviation [RSD] < 7.4) were obtained in different matrices. The method offered a good linearity with correlations of determination (R-2) higher than 0.9944 and was applied for determination and quantification of the analytes in some real samples. Finally, satisfactory results were obtained. (C) 2013 Elsevier Inc. All rights reserved.