Correlation between physicochemical properties and non-covalent interactions involving l-arginine/l-histidine and semicarbazide hydrochloride at temperatures from 293.15 to 318.15 K

Physicochemical properties and the nature of interaction of drug-amino acid have been investigated from the experimentally measured values of densities, rho, ultrasonic speed, u and viscosities, eta of l-arginine and l-histidine in aqueous-semicarbazide hydrochloride (1 wt% and 2 wt% semicarbazide hydrochloride in water, w/w) solvents over the temperature range of 293.15 K to 318.15 K at an interval of 5 K and at atmospheric pressure. From the experimental densities, the apparent molar volume, Vu, limiting apparent molar volume, V-phi(0) and transfer volume, V-phi,tr(0) were obtained. Further from the ultrasonic data, thermo-acoustical parameters, such as apparent molar compressibility, K-s,K-phi limiting apparent molar compressibility, K-s,phi(0) and transfer compressibility, K-s,phi,tr(0) have been evaluated. The viscosity data have been used to determine Falkenhagen Coefficient, A, Jones-Dole coefficient, B, free energy of activation of viscous flow per mole of solvent, Delta mu(o#)(1) and solute, Delta mu(o#)(2), entropies, Delta S-o# and enthalpies, Delta H-o# of activation of viscous flow. The results have been interpreted in terms of plausible molecular interactions. The cosphere overlap model has been used to interpret the positive V-phi,tr(0) values. These amino acids act as structure maker in aqueous-semicarbazide hydrochloride solvents. (C) 2020 Elsevier Ltd.