Determination of baclofen enantiomers in pharmaceutical formulations using maltodextrin-based enantioselective, potentiometric membrane electrodes

Abstract

Two enantioselective, potentiometric membrane electrodes (EPMEs) based on maltodextrins with different value of dextrose equivalent (DE) (maltodextrin I: DE 4.0-7.0; maltodextrin II: DE 16.5-19.5) were proposed for the assay of baclofen enantiomers in baclofen raw materials and from its pharmaceutical formulation, Norton-Baclofen ® tablets. The slopes of the electrode function of the proposed electrodes were 55.0 mV/p S-baclofen for maltodextrin I-based electrode and 59.0 mV/p R-baclofen for maltodextrin II-based electrode and the detection limits were 1.34 × 10 –6 mol l –1 ( S-baclofen) and 2.52 × 10 –10 mol l –1 ( R-baclofen), respectively. The surfaces of the electrodes are stable and easily renewable by simply polishing on alumina paper.