Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

Apparent molar properties (Vpounds and Kpounds;s) of amino acids (glycine, L-alanine and L-valine) within the concentration range of (0.02-0.20) mol kg-1 in aqueous (0.005, 0.01 and 0.03) mol kg-1 Levofloxacin (LVFX) solutions are computed from the experimental density oqP and ultrasonic speed ocP values at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K and P = 0.1 MPa. Derived parameters such as partial molar properties oV0 pounds and K0 pounds;s P and their experimental slopes oSV and SK P, transfer partial molar properties (DV0 pounds and DK0 pounds;s), hydration numbers onHP and Hepler s constant are computed from the data of apparent molar properties. The pair and triplet interaction coefficients have also been evaluated from transfer parameters. The linear variation of V0 pounds with the number of carbon atoms in the alkyl chain of amino acids has been utilized to calculate the contribution of the charged end groups oNHp 3 ; COO P, oCH2P group and other alkyl chains of the amino acids to V0 pounds. From the obtained parameters, some information in regard with the solute-solvent interaction in the systems studied was obtained. The co-sphere overlap model was used to interpret the positive transfer properties (DV0 pounds and DK0 pounds;s). The volume and compression data suggest that there exist strong solute-solvent interactions in these systems, which increase with increase in temperature. It is inferred that amino acids studied act as structure-breaker (chaotropic effect) in aqueous LVFX solutions.