Apparent Molar Properties of 1-Dodecyl-3-methylimidazolium Bromide Ionic Liquid in the Presence of Aqueous Solution Containing Glycyl-L-X (X = Alanine and Phenylalanine) Dipeptides

Significant advancements have been made in the last several years with regard to the manufacturing, composition, and extraction of active medicinal substances. Thorough thermodynamic investigations provide comprehensive insights into these interactions, aiding in the selection of appropriate compounds within the pharmaceutical realm. Notably, the analysis of IL–biomolecule interactions in aqueous solutions is pivotal across various research domains, given that the IL exerts its influence by interacting with biological membranes. This study focuses on assessing the density and speed of sound for [C12Mim] Br, in aqueous solutions containing dipeptide glycyl-X (X = l-alanine and l-phenylalanine) over the temperature range of 288.15–318.15 K and at an experimental pressure, p = 0.1 MPa. Through the correlation of measured physical parameters with established relationships, the apparent molar volumes (Vϕ) and apparent molar isentropic compressions (Kϕ,s) were determined. Furthermore, calculations were performed to limit apparent molar expansibilities at infinite dilution (ϕE0) and Hepler's constant. The Redlich–Mayer equation was employed to fit the experimental data, facilitating the determination of essential parameters, including partial molar volume (Vϕ0), and limiting isentropic compression (Kϕ,s0). Interactions coefficients were computed using partial molar volume of transfer and the partial molar isentropic compression of transfer.