THERMODYNAMIC INVESTIGATIONS OF INTERACTIONS IN AQUEOUS-SOLUTIONS OF GLYCINE AND SOME SMALL PEPTIDES WITH CAFFEINE AND 1,3-DIMETHYLURACIL AT 298.15 K

Enthalpies of dilution for ternary aqueous solutions of glycine, glycy l-glycine, triglycine, and L-alpha-alanyl-L-alpha-alanine with caffein e, as well as of glycyl-glycine, and L-alpha-alanyl-L-alpha-alanine wi th 1,3-dimethyluracil have been determined. The results have been anal ysed in terms of the McMillan-Mayer formalism in order to obtain the e nthalpic virial coefficients. Weak interactions were observed. The den sities and molar volumes at infinite dilution were determined for the systems mentioned, as well as for aqueous solutions of glycine, glycyl -glycine and triglycine.