Physicochemical investigation on interactions of some amino acids with aqueous tetra-butyl ammonium bromide solution at 298.15 K

Abstract

Apparent molar volumes, viscosity B-coefficients, and apparent molar isentropic compressibilities of glycine, L-alanine, L-valine and L-leucine in 0.062, 0.125 and 0.256 mol kg−1 aqueous tetra-butyl ammonium bromide (TBAB) solution have been determined at 298.15 K from their experimental density, flow time and sound speed measurements, respectively. The standard partial molar volumes and compressibilities are used to calculate the corresponding volume of transfer at infinite dilution, from water to aqueous TBAB solutions. The linear correlation of partial molar volumes for a homologous series of amino acids has been utilised to calculate the contribution of charged end groups and other alkyl chains of the amino acids to partial molar volumes. The hydration numbers of amino acids have also been determined. Viscosity B-coefficients have been calculated using the Jones–Dole equation. The values of the charged end groups contribution to the viscosity B-coefficients of the amino acids are calculated.