Author(s): Saad S.M. Hassan
Article publication date: 1986-06-01
Vol. 4 No. 1 (yearly), pp. 133-143.
127
Keywords
electrode, ion, inorganic cations
Abstract
A new liquid membrane electrode based on an ion-association extraction system responding to ephedrine is described. It incorporates ephedrine-5- nitro barbiturate ion pair complex in octan-1-ol as a novel electroactive component. The electrode exhibits Nernstian response over the concentration range of 10^-2 to 10^-6 M ephedrine in solutions of pH 4-9. The response time varies from 20 to 90 seconds and interferences from many organix bases and some common inorganic cations are negligible. Determination of 0.1 to 2000 micrograms/ml ephedrine in both pure and pharmaceutical samples gives results with an average recovery of 99.2% and a mean standard deviation of 1.5%.