TY - JOUR
T1 - Influence of biocompatible ammonium ionic liquids on the solubility of l-alanine and l-valine in water
AU - Vasantha, T.
AU - Kumar, Awanish
AU - Attri, Pankaj
AU - Venkatesu, Pannuru
AU - Rama Devi, R. S.
N1 - Funding Information:
We are gratefully acknowledged the University Grants Commission (UGC), New Delhi , Council of Scientific Industrial Research (CSIR), New Delhi , through the Grant No. 01(2343)/09/EMR-II and Department of Science and Technology (DST), New Delhi, India for financial support.
PY - 2012/12/15
Y1 - 2012/12/15
N2 - Understanding the folding process of proteins or polypeptides in co-solvents is a fascinating and critical issue in biophysical chemistry. In recent years, ionic liquids (ILs) represent a versatility of the new class of co-solvents. To quantify the bimolecular interactions of amino acids (AA), such as l-alanine (Ala) and l-valine (Val) with biocompatible ILs, we report the apparent transfer free energies (ΔG'tr) for AA from water to aqueous solutions of six ammonium based ILs (diethylammonium acetate (DEAA), diethylammonium sulfate (DEAS), triethyl ammonium acetate (TEAA), triethylammonium sulfate (TEAS), triethylammonium dihydrogen phosphate (TEAP), and trimethylammonium acetate (TMAA)) through solubility measurements, as a function of IL concentration at 298.15. K under atmospheric pressure. Salting-out effect was found for AA in aqueous IL solutions with increasing IL concentrations. In addition, we observed positive values of ΔG'tr for Ala and Val from water to ILs, indicating that the interactions between ILs and AA are unfavorable. From the solubility results, we envisage that the selected ammonium based-ILs provide stability to the structure of AA. Further, the stability of AA has been studied by means of the UV-vis spectroscopy.
AB - Understanding the folding process of proteins or polypeptides in co-solvents is a fascinating and critical issue in biophysical chemistry. In recent years, ionic liquids (ILs) represent a versatility of the new class of co-solvents. To quantify the bimolecular interactions of amino acids (AA), such as l-alanine (Ala) and l-valine (Val) with biocompatible ILs, we report the apparent transfer free energies (ΔG'tr) for AA from water to aqueous solutions of six ammonium based ILs (diethylammonium acetate (DEAA), diethylammonium sulfate (DEAS), triethyl ammonium acetate (TEAA), triethylammonium sulfate (TEAS), triethylammonium dihydrogen phosphate (TEAP), and trimethylammonium acetate (TMAA)) through solubility measurements, as a function of IL concentration at 298.15. K under atmospheric pressure. Salting-out effect was found for AA in aqueous IL solutions with increasing IL concentrations. In addition, we observed positive values of ΔG'tr for Ala and Val from water to ILs, indicating that the interactions between ILs and AA are unfavorable. From the solubility results, we envisage that the selected ammonium based-ILs provide stability to the structure of AA. Further, the stability of AA has been studied by means of the UV-vis spectroscopy.
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U2 - 10.1016/j.fluid.2012.08.021
DO - 10.1016/j.fluid.2012.08.021
M3 - Article
AN - SCOPUS:84865964600
SN - 0378-3812
VL - 335
SP - 39
EP - 45
JO - Fluid Phase Equilibria
JF - Fluid Phase Equilibria
ER -