Thermodynamic study of calcium d-pantothenate drug in the presence of aqueous solutions including some amino acids: Volumetric and compressibility properties

Abstract

The impressive and remarkable efforts have been made over the past years to improve the production, formulation and purification of active ingredients pharmaceutical which leads to the discovery of novel drug preparations and delivery systems. The optimal design of such processes requires a molecular-level understanding of the interactions between drug molecules and biological membranes. The thermodynamic investigation provides deep and complete knowledge of interactions and the choice of appropriate and suitable compounds in pharmaceutical fields. Particularly, the analysis of drugs + biomolecules in aqueous solutions is the central issue in many types of research because they exert their impact by interacting with biological membranes. This work is aimed to measure the density and speed of sound for the calcium d-pantothenate, vitamin B5 calcium salt (CDP) in aqueous solutions of amino acids (glycine, l-alanine, and l-leucine) at temperature ranges (293.15 to 308.15) K. By correlating of the measured physical quantities in with standard relations, apparent molar volumes, Vϕ,m, and apparent molar isentropic compression, κs,ϕ,m, are calculated. In addition, apparent molar isobaric expansion, Eϕ,m0, and Hepler’s constant are computed. For fitting the experimental Vϕ,m and κϕ the Redlich-Meyer equation was employed that the important quantities; standard partial molar volume, Vϕ0 , and partial molar isentropic compression, κϕ0, were obtained.