Assay of procyclidine hydrochloride, cyclizine hydrochloride and diethylcarbamazine citrate in tablets using ion-responsive electrodes
Plastic electrodes responding to organic ions have been prepared by coating a plasticised PVC film on to a graphite support. The incorporation of nitrobenzene as plasticiser gave an electrode responding to anions. Electrodes containing both nitrobenzene and bis(2-ethylhexyl) phthalate responded to both anions and cations, whilst giving a negligible response to pH change. The electrodes were used to monitor the titrations of amines with sodium tetraphenylborate. For the titration of procyclidine and cyclizine an electrode that responds to both anions and cations gives a larger potential change than an electrode that responds to only one of the reacting ions. Methods for the assay of procyclidine hydrochloride, cyclizine hydrochloride and diethylcarbamazine citrate in tablets are described.