Simultaneous determination of acidic and basic drugs using dual hollow fibre electromembrane extraction combined with...

The simultaneous extraction of acidic and basic drugs from biological samples is a significant challenge for sample preparation. A novel and efficient method named dual hollow fibre electromembrane extraction combined with CE was applied for the simultaneous extraction and preconcentration of acidic and basic drugs in a single step. Under applied potential of 40 V during the extraction, ibuprofen as an acidic drug and thebaine as a basic drug migrated from a 4 mL aqueous sample solution at neutral pH into 20 μL of each basic (pH 12.5) and acidic (pH 2.0) acceptor phase, respectively; 1-octanol and 2-nitrophenyl octyl ether were immobilised in the pores of anodic and cathodic hollow fibres as supported liquid membranes, respectively. A Box-Behnken design and the response surface methodology were used for the optimisation of different parameters on the extraction efficiency. Under the optimised conditions, the enrichment factors were between 150 and 170 and also the LODs ranged from 3 to 7 ng/mL in different samples. The method was reproducible so that intra- and inter-day RSDs% (n = 5) were less than 5.9%. Finally, the method was successfully applied for the simultaneous extraction and determination of acidic and basic drugs from plasma and urine samples.