Keywords: Amino acid; aqueous solution; drug, molecular interaction; physicochemical properties

Abstract

In drug development, the interactions between drugs and proteins are vital because they determine efficacy. However, due to the complex configurational and conformational structures of native globular protein molecules, it is difficult to understand their structural features. It is known that hydrophilic and hydrophobic groups as well as dipolar water interactions play a crucial role in the stability and structural properties of proteins as most biochemical and physiological processes occur in the aqueous medium. Such interactions may be understood via thermodynamic properties such as partial molar volume and compressibility. Thus, amino acids, simple monomer building blocks that mimic aspects of proteins, are used by researchers as model compounds to understand protein-drug interactions and protein hydration. This review surveys the thermodynamic properties of amino acids in drug solutions at various temperatures as they are crucial in interpreting the hydration of peptides and proteins. Past studies of amino acids in aqueous drug solutions at different temperatures are also discussed and summarised.