Solvation free energies in [bmim]-based ionic liquids: Anion effect toward solvation of amino acid side chain analogues

Stochastic molecular dynamics simulations were performed to investigate the solvation free energy of 15 neutral amino acid side chain analogues in aqueous and five, 1-butyl-3-methylimidazolium ([BMIM])-based ionic liquids. The results in aqueous were found highly correlated with previous experimental and simulation data. Meanwhile, [BMIM]-based RTILs showed better solvation thermodynamics than water to an extent that they were capable of solvating molecules immiscible in water. Non-polar analogues showed stronger solvation in hydrophobic RTIL anions such as [PF6]− and [Tf2N]− while polar analogues showed stronger solvation in the more hydrophilic RTIL anions such as [Cl]−, [TfO]− and [BF4]−.