Interaction of Aqueous Solution of Sulphamethoxazole Drug with Diglycine by Volumetric Method at Different Temperatures

Abstract

Abstract The interaction of diglycine with sulphamethoxazole drug as a function of temperature and concentration have been investigated by volumetric method. The density of ternary mixture of diglycine (0.002–0.01 mol  ·  kg –1) in aqueous sulphamethoxazole drug (0.001–0.01 mol  ·  kg –1) solution have been measured using Anton Paar DSA 5000 instrument at T = (288.15  to  308.15) K. The apparent molar volumes V φ , partial molar volume at infinite dilution V φ 0, transfer partial molar volume Δ tr V φ ○, partial molar expansibility E 2 o , thermal expansion coefficient α 2, and Hepler's constant (∂C P ∞/∂P) T are calculated from density data. The above parameters are used to interpret the solute-solute and solute-solvent interactions of diglycine in aqueous solution of sulphamethoxazole drug. Hydration number and interaction coefficients have also been calculated from these data. Dehydration of diglycine is observed, rising with the temperature and drug molality. These results are explained on the basis of drug-water-amino acid interactions. The data suggest that interaction between ions and charged/hydrophilic groups are predominant.