Theoretical study of the interaction of lactose with collagen, the electronic and mechanical properties of crystalline lactose

Abstract

We studied elastic and electronic properties of α- and β-lactose crystals within the framework of density functional theory with van der Waals interactions. The calculated values of lattice parameters have good agreement with the experimental data. The interaction energies of α- and β-lactose molecules with collagen protein were also calculated, which are equal to 4.2 and 4.1 kcal/mol, respectively. Complete set of elastic constants for α- and β-lactose were calculated. It has been established that mechanical properties of these crystals are different. Our calculations predict that α-lactose is ductile compound, while β-lactose is brittle compound. Topological properties of hydrogen bonds of the crystals were studied using the quantum theory of atoms in molecules (QTAIM). Thus, the differences between the α- and β-lactose molecules are manifested in the molecules interaction in the crystal resulting in the differences of macrocharacteristics of these crystals.