Enantioselective, potentiometric membrane electrodes based on cyclodextrins: application for the determination of R-baclofen in its pharmaceutical formulation.
Two enantioselective, potentiometric membrane electrodes based on alpha- and gamma-cyclodextrins were proposed for the assay of R-baclofen. The slopes of the electrodes were 59.50 and 51.00 mV/pR-baclofen for alpha- and gamma-cyclodextrin-based electrodes, respectively. The detection limits of the proposed electrodes were 7 x 10(-9)mol l(-1) for alpha-cyclodextrin-based electrode and 1.44 x 10(-10)mol l(-1) for gamma-cyclodextrin-based electrode. The enantioselectivity was determined over S-baclofen. The proposed electrodes can be employed for the assay of R-baclofen raw materials and its pharmaceutical formulation, Norton-Baclofen tablets. The surfaces of the electrodes are stable and easily renewable by polishing on alumina paper.
Stefan van Staden
Raluca-Ioana
RI
Department of Chemistry, University of Pretoria, Pretoria, South Africa. Raluca.Stefan@chem.up.ac.za
Rat'ko
Alexander A
AA