Viscosity B-coefficients and standard partial molar volumes of amino acids, and their roles in interpreting the protein (enzyme) stabilization

Investigation on molecular interaction of amino acids in antibacterial drug ampicillin solutions with reference to volumetric and compressibility measurements

A comparative study of the volumetric properties of dilute aqueous solutions of 1-propanol, 1,2-propanediol, 1,3-propanediol, and 1,2,3-propanetriol at various temperatures

Density (ρ), speed of sound (u), and viscosity (η) measurements of amino acids l-glutamine and l-histidine in aqueous solutions of metformin hydrochloride (an antidiabetic drug) (0.01, 0.07, and 0.13 mol·kg–1) were carried out in the concentration range (0.02–0.20 mol·kg–1) at 293.15, 298.15, 303.15, 308.15, and 313.15 K. The experimental data has been meticulously used to enumerate various parameters which assist to procure valuable information regarding the presence of different kinds of intermolecular interactions present in the ternary (metformin hydrochloride + water + amino acids) system. The results were interpreted in terms of various metformin hydrochloride–amino acid intermolecular interactions through a cosphere overlap model. The ion–ion interactions are the key players in ternary system and these interactions are of higher order in the case of histidine as compared to glutamine. Also application of transition state theory has been made to calculate the thermodynamic activation parameters for ...

Drug−Amino Acid Interactions in Aqueous Medium: Volumetric, Compressibility, and Viscometric Studies

Effect of l-serine and l-threonine on volumetric and acoustic behaviour of aqueous metformin hydrochloride solutions at T = (305.15, 310.15 and 315.15) K

In this work, we present experimental results for partial molar volumes and viscosities of aqueous solutions of α-dl-aminobutyric acid, dl-norvaline and dl-norleucine at 288.15, 293.15, 298.15 and 303.15 K. The thermodynamic behavior of aqueous amino acid solutions is compared with that reported for glycine and α-alanine in water and is discussed in terms of group additivity and electrostriction. The temperature dependence of the infinite dilution partial molar volumes and the B viscosity coefficients are interpreted in terms of amino acid hydration. According to the usual hydrophobicity criteria, the amino acids considered do not have a hydrophobic character and their behavior is dominated by the polar groups.

Faustino Negrete

Papers

Effect of temperature on partial molar volumes and viscosities of aqueous solutions of α-dl-Aminobutyric acid, dl-Norvaline and dl-Norleucine

Effect of temperature on the volumetric properties of dilute aqueous solutions of 1,2-hexanediol, 1,5-hexanediol, 1,6-hexanediol, and 2,5-hexanediol