Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

Various non-covalent interactions can be scrutinized by the measurement of physical properties. The nature of interactions between drugs and amino acids governs the functionalization process, so a better understanding demands reliable thermophysical data. Keeping this in mind, we report herein the densities, rho, ultrasonic speed, u and viscosities, eta of glycine, l-alanine, l-valine and l-isoleucine in aqueous-semicarbazide hydrochloride (1 wt% and 2 wt% semicarbazide hydrochloride in water) solvents in the temperature range of 293.15-318.15 K at an interval of 5 K and at atmospheric pressure. The density data have been used to calculate the apparent molar properties like Vphi, Vphi.deg. and transfer volume, Vphi,tr.deg.. From the ultrasonic speed data, thermo-acoustical parameters, such as Ks,phi, Ks,phi.deg. and transfer compressibility, Ks,phi,tr.deg. have been evaluated. The viscosity data have been used to calculate Falkenhagen Coefficient, A, Jones-Dole coefficient, B. The hydration numbers, nH has also been evaluated. The entropies, deltaS.deg. and enthalpies, deltaH.deg. activation parameters, deltamu1.deg. and deltamu2.deg. were also calculated. The co-sphere overlap model was used to interpret the positive Vphi,tr.deg. values. In addition, the values of Vphi.deg., Ks,phi.deg., B and deltamu2.deg. have been split into groups' contributions of the amino acids.