Journal of Bioequivalence & Bioavailability

Abstract

Novel Coated Wires Sensors with Flow-Injection for Potentiometric Determination of Neostigmine in Bulk, Amostigmine and Human Urine

Khorshid AF and Issa YM

Four types of coated wires sensors (silver, copper, graphite and glassy carbon) are constructed for the determination of neostigmine (Ns) based on the ion-pair associates neostigmine silicotungstate (Ns-ST), neostigmine silicomolybdate (Ns-SM), neostigmine phosphotungstate (Ns-PT), neostigmine phospho molybdate (Ns-PM),and ion-pairs neostigmine tetraphenylborate (Ns-TPB) in a poly (vinyl chloride) as coated film with a plasticized tricresylphthalate (TCP). The four types sensors are showed a Nernstain slopes ranged from 59-64 mV per decade in batch and 65-70 mV per decade in flow injection conditions (FIA) over a neostigmine concentration ranged from 5.0x10-7-1.0x10-2 M and within the pH range 4.0-11.0. The influences of coated film composition, pH of the Ns and foreign ions on the sensors performance were investigated and were found to be very selective, precise and excellent selectivity. The sensors were successfully applied to the potentiometric determination of neostigmine bromide in pure state, in amostigmine, and human urine. FI analysis and dissolution profile for determination neostigmine were investigated. The data were comparable with official methods for the assay and excellent percentage recovery was obtained.