Solubilities of Pharmaceutical Compounds in Ionic Liquids

The solubilities of paracetamol and ibuprofen were determined in two different ionic liquids at temperatures of 298.15 K, 308.15 K, 318.15 K, 328.15 K, and 338.15 K. The ionic liquids selected were 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6] and 1-hexyl-3-methylimidazolium hexafluorophosphate [HMIM][PF6]. In addition, solubility data for paracetamol and ibuprofen in water are reported at the same temperatures extending the data commonly reported in pharmaceutical reference texts. For all solvents the concentration of drug in solution was determined by UV spectrophotometry.