Enantioselective, Potentiometric Membrane Electrodes (EPME) Based on Maltodextrins for the Determination of L-Vesamicol in Serum Samples

Raluca-Ioana      Stefan-van Staden; R'afat      M. Nejem; Jacobus      F. van Staden; Hassan      Y. Aboul-Enein

Abstract

Three EPMEs based on maltodextrins with different dextrose equivalent (DE) values [I (4.0-7.0), II (13.0-17.0) and III (16.5-19.5)], were designed for the determination of L-vesamicol. The linear concentration ranges of the proposed electrodes were 10-4 - 10-2 mol/L for maltodextrin I-based electrode, 10-5 -10-3 mol/L for maltodextrin II-based electrode and 10-9 - 10-7 mol/L for maltodextrin III-based electrode. The detection limits of the proposed electrodes were 1.34x10-5, 5.0x10-6 and 3.33x10-10 mol/L for maltodextrin I, II and III based electrodes, respectively. The selectivity of EPMEs for L-vesamicol was tested over D-vesamicol, creatine, creatinine and some inorganic ions. The surfaces of the electrodes can be easily renewed by simply polishing on alumina.

Keywords: Enantioselective, Potentiometric membrane electrode, Maltodextrins, L-vesamicol, Alzheimer's disease, Ag/AgCl electrode, Parkinson's disease, Down's Syndrome, Olivopontocerebellar atrophy, Electrophoresis