Construction of Modified Screen-Printed and Carbon Paste Electrodes for Electrochemical Determination of Antihistaminic Diphenhydramine Hydrochloride in Pure and Pharmaceutical Preparations

• Published in: International journal of electrochemical science 2013-09, Vol.8 (9), p.11546-11563
• Main Authors: Akl, M.A., Frag, Eman Y.Z., Mohamed, Gehad G., Bashanaini, Mohammed S.A.
• Format: Article
• Language: English
• Subjects: capsules; diphenhydramine; ICPE; ISPE; Potentiometry
• ISSN: 1452-3981; 1452-3981
• DOI: 10.1016/S1452-3981(23)13203-2

The construction and performance characteristics of diphenhydramine hydrochloride (DPH) modified screen printed (SPE) and carbon paste (CPE) electrodes with DPH-tetrapheylborate ion pair (DPH-TPB) (MSPE and MCPE) and with sodium tetraphenyl borate ion pairing agent (NaTPB) (in situ) (ISPE and ICPE) using tricrysylphosphate (TCP) as plasticizer are described. These electrodes exhibit suitable response to DPH in the concentration range of 1x10-1 to 1x10-6 mol L-1 with lower detection limit of 9.65x10-7, 9.68x10-7, 9.78x10-7 and 9.76x10-7 mol L-1 and response time of about 5, 6, 10 and 11s with Nernstian slope values of 56.20±0.65, 59.14±0.90, 55.86±1.12 and 60.03±1.32 mV decade-1 for MSPE, ISPE, MCPE and ICPE, respectively. The fabricated electrodes were used over a period of 2 months under pH range of 2.5-8.0, 3.0-9.0, 2.5-7.0 and 3.0-8.0 for MSPE, ISPE, MCPE and ICPE, respectively. The analytical performance of the SPEs and CPEs compared with respect to selectivity coefficients for DPH relative to a numbers of potential interfering substances were investigated. The method was applied for determination of DPH in pharmaceutical preparations with a percentage recovery of 98.75-99.27, 98.95-99.66, 98.91-99.65 and 97.83-99.17% and and R.S.D = 0.54, 0.29, 0.26 and 0.56 for MSPE, ISPE, MCPE and ICPE, respectively. The results are compared with the official method.