Effect of ranitidine hydrochloride on water activity in ternary aqueous solutions containing drug and ionic liquid based on vapor liquid equilibria at 298.15 K

Vapor-liquid equilibrium (VLE) studies were carried out to investigate the influence of ranitidine hydrochloride (Rani-HCl) on the thermodynamic behavior of aqueous solutions containing various pharmaceutical compounds and ionic liquids (ILs). The drugs examined alongside Rani-HCl included diphenhydramine hydrochloride (DPH-HCl), guaifenesin (GFN), and naproxen sodium (NS), while the selected ILs were 1-butyl-3-methylimidazolium chloride ([BMIm]Cl), 1-butyl-3-methylimidazolium bromide ([BMIm]Br), and 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate ([BMP][TfO]). VLE measurements were performed using the isopiestic method at a constant temperature of 298.15 K. To analyze the data, several local composition models-TNRF-mNRTL, NRTL, NRF-NRTL, mNRTL, and Wilson-were employed to compute key VLE parameters such as activity coefficients and vapor pressures for both binary and ternary systems. The resulting data, together with their thermodynamic interpretations, provided valuable insights into the nature and extent of solute-solvent interactions within the studied mixtures.