Thermophysical Studies on Molecular Interactions of Semicarbazide Hydrochloride/Domiphen Bromide in Aqueous Deep Eutectic Solvent Media at Various Temperatures
Qammer Majid, Richu, Himani Singh, Akshita Bandral, Ashwani Kumar
Abstract
A comprehensive examination of the thermophysical properties of semicarbazide hydrochloride and domiphen bromide in water and aqueous maline solutions (maline, a deep eutectic solvent (DES) made by mixing choline chloride and malonic acid in 1:2 mol ratio) has been done by a combination of ultrasonic, volumetric, viscometric, and thermodynamic methods at the temperature range from 293.15 to 318.15 K. Exploration of molecular interactions through the procured thermophysical properties is very important because it provides an insight into the forces that are operating in the liquid mixtures. In the present study, thermophysical parameters such as apparent molar volume (Vϕ), apparent molar isentropic compressibility (Kϕ,s), viscosity coefficients, Hepler’s constant, etc. are studied for the above-mentioned drugs in water and aqueous maline solutions. The results revealed the dominance of solute–solvent interactions in the studied systems, which were found to escalate with elevation in temperature and with the concentration of maline. The results are discussed in terms of hydrophilic–hydrophilic and hydrophilic–hydrophobic interactions in these systems along with the structure breaking/making ability of the drugs. The co-sphere overlap model has been used to interpret the positive transfer values.