Development of two ion-selective sensors for determining benzydamine hydrochloride in the presence of its oxidative degradant across various matrices: greenness, whiteness, and blueness appraisals

Two sensitive and selective ion-selective electrodes (ISEs) were developed for the determination of benzydamine hydrochloride (BNZ·HCl): a conventional polyvinyl chloride (PVC) electrode and a coated graphite all solidstate ion-selective electrode (ASS-ISE). Both sensors were constructed using an ion-pair formed between BNZ⁺ and the lipophilic anion tetraphenylborate (TPB⁻), incorporated into the sensing membranes. The sensors exhibited near-Nernstian responses with slopes of 58.09 And 57.88 mV/decade, over a Linear range of 10^-5-10^-2 M, and detection Limits of 5.81 × 10^-8M and 7.41 × 10^-8 M, respectively. They demonstrated high accuracy and precision for the determination of BNZ·HCl in pure form, pharmaceutical cream, and biological fluids, with no matrix interference. The method also proved stability-indicating, successfully detecting BNZ·HCl in the presence of its oxidative degradant. Validation was performed according to ICH guidelines, and the method showed strong environmental compatibility based on greenness, whiteness, and blueness assessments, supporting its suitability for sustainable pharmaceutical analysis.