Modified Screen Printed and Carbon Paste Ion Selective Electrodes for Potentiometric Determination of Naphazoline Hydrochloride in Pure and Pharmaceutical Preparations

• Published in: International journal of electrochemical science Vol. 7; no. 10; pp. 10266 - 10281
• Main Authors: El-Dien, F.A. Nour, Mohamed, Gehad G., Frag, Eman Y.Z., Mohamed, Marwa El-Badry
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2012
• Subjects: calibration; method validation; Modified screen printed and carbon paste electrodes; Naphazoline hydrochloride; Modified screen printed and carbon paste electrodes; method validation; Naphazoline hydrochloride; calibration
• ISSN: 1452-3981; 1452-3981
• DOI: 10.1016/S1452-3981(23)16275-4

In this study, a comparison between modified screen printed (SPE) and carbon paste (CPE) electrodes is described for determination of naphazoline hydrochloride in pure and pharmaceutical formulations. The performance characteristics of the electrodes were evaluated in terms of composition, life span, pH, and temperature. The electrodes show Nernstian slope values of 55.4±2.2 and 59.6±1.3 mV decade-1 at 25 oC, over the concentration ranges of 5.0x10-7 – 3.5x10-2 and 3.0x10-7 – 2.5x10-2 mol L-1 with a limit of detection of 2.512x10-7 and 3.162x10-7 mol L-1 for modified SPE and CPE, respectively. The potentiometric response of the electrodes is independent of the pH of the solution within the pH range of 2.5-8.5 and 2.7-8.5 for modified SPE and CPE, respectively. The electrodes showed good selectivity for naphazoline hydrochloride (NPZ.HCl) with respect to some inorganic cations, sugars and glycine. The electrodes exhibited relatively long operational lifetime of 47 and 32 days for modified SPE and CPE sensors, respectively. The developed modified sensors have been used successfully for the determination of naphazoline hydrochloride in pharmaceutical preparation using standard addition, potentiometric titration and calibration methods. The direct potentiometric determination of naphazoline hydrochloride using the prepared sensors gave recoveries 98% and 97.4% using modified SPE and CPE, respectively. The method avoids any interference of coexistent NPZ.HCl in the compounding drug. The obtained results were in a good agreement with those obtained using the official method. The results obtained were satisfactory with excellent percentage recovery comparable and sometimes better than those obtained by other routine methods for the assay.