INTERACTION OF SOME BIOMOLECULES WITH MODIFIED NANOSILICA SURFACES STUDIED BY QUANTUM CHEMISTRY

摘要

The equilibrium geometries and heat of adsorption values for some complexes of amino acids and the helical section of human serum albumin on a silica surface, in both gaseous phase and water solutions, have been calculated using quantum chemical methods. In this study a suitable method is proposed for calculating the interaction energy. A probable mechanism has been suggested for the interaction between a hydroxylated silica nanoparticle, with negative surface charge, and lipid molecules. As both interacting species have the (negative) charge, and experiment gives evidence of their cohesion, in order to provide converging clusters we believe that hydronium ions are stationed between these species. If the total charge of this supramolecular structure is assumed to be zero, an optimization of geometric parameters results in the formation of a water-bonded complex.