Adsorption of Guanine on Oxygen-Deficient TiO2 Surface: A Combined MD-DFTB/DFT Strategy

Identifier:  imarina:9380941

Handle: https://hdl.handle.net/20.500.11797/imarina9380941

Authors:  Çetin, YA; Martorell, B; Serratosa, F; Calatayud, M

Abstract:
Metal oxides (MOs) are key materials in many fields, including technological, industrial, and biomedical applications. In most of these implementations, surface reactivity and reducibility properties are critical considerations. In their nanosized form, MOs exhibit enhanced reactivity that is connected to toxicity. Besides the fact that the biological molecule and the surface of the corresponding material interact chemically, little is known about the toxicological mechanisms involved on the atomic scale. The goal of this study is to investigate the role of TiO2 surfaces in interaction with one genetic base, namely guanine. Using a combination of the quasi-electronic density functional-tight binding molecular dynamics simulations and density functional theory calculations, we explored the adsorption modes of guanine with a stoichiometric and oxygen-deficient anatase TiO2 (101) surface. With such an approach, we have characterized new adsorption modes not previously found, and we have highlighted the relevance of defective surfaces in the adsorption of genetic basis, as a model for explaining possible toxicology mechanisms induced by the adsorption process.