Construction and Performance Characterization of Ion Selective Electrodes for Potentiometric Determination of Ranitidine Hydrochloride in Pharmaceutical Preparations and Biological Fluids

• Published in: International journal of electrochemical science 2011-08, Vol.6 (8), p.3508-3524
• Main Authors: Frag, Eman Y.Z., Mohamed, Ahmed M.K., Mohamed, Gehad G., Alrahmony, Ebtesam E.
• Format: Article
• Language: English
• Subjects: Carbon paste electrode; potentiometric titration; ranitidine hydrochloride; screen printed electrode; serum; tablets; urine
• ISSN: 1452-3981; 1452-3981
• DOI: 10.1016/S1452-3981(23)18268-X

The construction and performance characteristics of ranitidine hydrochloride (RNH) selective electrodes are described. Two types of electrodes: carbon paste and screen printed electrodes were constructed based on the ion-pair formation during potentiometric titration of ranitidine hydrochloride with sodium tetraphenylborate. The electrodes were fully characterized in terms of plasticizer type, response time, lifetime, soaking, titrant, pH and temperature. The CPE and SPE electrodes exhibited Nernstian response for RNH in the concentration range from 1.0×10−7 to 1.0×10−2 and 1.0×10−7 to 1.0×10−2 mol L-1 with a slope of 55.74±1 and 58.89±1.2 mV decade-1, respectively. The detection limit and quantification are found to be 0.07×10-7 and 0.23×10-7 and 0.09×10-7 and 0.32×10-7 mol L-1 for CPE and SPE, respectively. The standard electrode potentials, E°, were determined at 10, 25, 30, 40 and 50 °C and used to calculate the isothermal temperature coefficient (dE°/dT) of the two electrodes. Temperatures higher than 50 °C seriously affect the electrodes performance. The direct potentiometric determination of RNH using the proposed sensors gave average recoveries % of 98.00±0.40-98.57±0.37 and 98.68±0.42-99.33±0.31 for CPE and SPE sensors, respectively. The electrodes were applied for potentiometric determination of RNH in pure state and pharmaceutical preparation under batch conditions, urine and serum. Interference studies from a large number of inorganic cations, sugars, glycine and drug excipients are reported. The electrodes gave average selective precision and were usable within the pH range 3-5 and 3-6 for CPE and SPE, respectively. The developed method was found to be simple, accurate and precise when compared with the reported method.