@article{article_1684403, title={Determination of protonation constant value of thiabendazole in ethanol-water binary mixtures by green RPLC method}, journal={Journal of Research in Pharmacy}, volume={28}, pages={40–50}, year={2025}, author={Kaplan, Sema Berfin and Konçe, İlkay and Çubuk Demiralay, Ebru}, keywords={Benzimidazole, pKa value, ethanol-water mixtures, modeling of retention}, abstract={In this study, an environmentally friendly analysis of an anti-infective/anthelmintic drug thiabendazole was carried out by liquid chromatography method using ethanol solvent that is not harmful to human health and the environment. Protonation constant ( 𝑝𝐾𝑎 𝑠 ) values of thiabendazole in 15, 20, 25, and 30% (v/v) ethanol-water binary 𝑠 mixtures at 37 oC were obtained by using the green reverse phase liquid chromatography method. The method is based on a model that relates the chromatographic behavior of the determined analytes to pH. The linear relationship between the solvatochromic parameter 𝐸𝑇 𝑁 and the retention values of the compound was determined depending on the variation of the organic solvent in the mobile phase. The relationship between the calculated 𝑠 value and the macroscopic 𝑠 𝑝𝐾𝑎 properties of ethanol was investigated. Compatibility was observed between the pKa ( 𝑝𝐾𝑎 𝑤 ) values in the aqueous 𝑤 medium determined by this linear approach. By using the 𝑤 value calculated for thiabendazole, the ionization 𝑤 𝑝𝐾𝑎 percentages were calculated at different pH (1-12) values with the Henderson-Hasselbalch equation.}, number={1}, publisher={Marmara University}