Open AccessPotentiometric pKa determination of biological active phenothiazine in different aqua-organic solvents
Author(s) -
Tanaji N. Bansode
Publication year - 2020
Publication title -
international journal of chemtech research
Language(s) - English
Resource type - Journals
eISSN - 2455-9555
pISSN - 0974-4290
DOI - 10.20902/ijctr.2019.130103
Subject(s) - potentiometric titration , chemistry , titration , phenothiazine , dissociation constant , ionic strength , acetonitrile , inorganic chemistry , organic solvent , solvent , aqueous solution , organic chemistry , ion , chemical engineering , medicine , biochemistry , receptor , engineering , pharmacology
Potentiometric titrations of phenothiazines derivatives were performed in methanolwater,ethanol-water, acetonitrile-water and dioxane-water mixtures with varying contents oforganic solvent. All titrations were performed in aqua-organic medium at constant ionicstrength (0.15 mol⋅dm−3) and at different temperatures (25 to 45 °C). The pKa weredetermined at different aqua-organic proportions. Effect of temperature and dielectric constanton dissociation constant has been compared. The pKa values were then obtained byYasuda‐Shedlovsky extrapolation.