https://rajpub.com/index.php/jac KHALSA PUBLICATIONS en-US JOURNAL OF ADVANCES IN CHEMISTRY 2321-807X <p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img src="https://i.creativecommons.org/l/by/4.0/88x31.png" alt="Creative Commons License" /></a> All articles published in <em>Journal of Advances in Linguistics</em> are licensed under a <a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>.</p> https://rajpub.com/index.php/jac/article/view/9378 <p><span style="font-weight: 400;">A new coated-wire electrode based on PVC membrane plasticized with dioctyl phthalate (DOP) and containing the diltiazem-tetraiodido bismuthate (III) ion association coated on a silver wire was constructed and used for potentiometric determination of diltiazem hydrochloride. The electrode performance was characterized and optimized according to the following experimental criteria: membrane composition, soaking time, working pH range, and response time. The interference caused by different species was investigated as well. The best membrane composition was found to be 49.75% of PVC and DOP, 0.5% ion pair. This sensor showed a linear response with a good Nernstian slope of 57.60±1.38 mV/decade over the concentration range</span><span style="font-weight: 400;"><br /></span><span style="font-weight: 400;">5.0×10</span><span style="font-weight: 400;">-5</span><span style="font-weight: 400;"> – 2.50×10</span><span style="font-weight: 400;">-2</span><span style="font-weight: 400;"> M, the detection limit was 2.88×10</span><span style="font-weight: 400;">-5 </span><span style="font-weight: 400;">M, and it was usable within a wide pH range of </span><span style="font-weight: 400;"><br /></span><span style="font-weight: 400;">2.5–8.0. The electrode showed a fast response time (18 sec), with a relative long lifetime (2.4 months, 2 h a day). The isothermal coefficient (dE°/dT) of the electrode was calculated and found to be 5.36×10</span><span style="font-weight: 400;">-4</span><span style="font-weight: 400;"> V/</span><span style="font-weight: 400;">℃</span><span style="font-weight: 400;"> within </span><span style="font-weight: 400;"><br /></span><span style="font-weight: 400;">20 – 80</span><span style="font-weight: 400;">℃</span><span style="font-weight: 400;">, which exhibits a good thermal stability. The coted-wire electrode was successfully applied for the potentiometric determination of diltiazem hydrochloride both in pure form and pharmaceutical preparations. The dissolution test of the drug was carried out as well.</span></p> Ryad Kassab Mahmoud Aboudan Copyright (c) 2023 Ryad Kassab, Mahmoud Aboudan https://creativecommons.org/licenses/by/4.0 2023-03-06 2023-03-06 19 1 9 10.24297/jac.v19i.9378