DFT study of amino-functionalized silica for ampicillin adsorption

E. NOSEDA GRAU; G. ROMAN; A. DIAZ COMPAÑY; S. SIMONETTI

Donostia-San Sebastián

Congreso; Quantum Thermodynamics of Non-Equilibrium Systems QTDNEQ20; 2020

Nanocarriers to transport substances are hopeful places to increase the enefcial treatment of medical drugs. Ampicillin is an extensive spectrum penicillin derivative used to treat several diseases and infections. Due to its great utility and small cost, ampicillin can e a model for a etter analysis of the adsorption processes of drugs in novel ceramic materials such as functionalized silica. The adsorption of ampicillin drug on SiO2(001) and SiO2(111) hydroxylated surfaces have been studied y DFT calculations that have ecome an important tool to understand the ehavior of materials. In this work, the improvement on adsorption when the system is functionalized with amino groups, are analyzed. The changes on adsorption of the pH dependence-ampicillinspecies are studied. Ampicillin molecule approaches on oth surfaces via N and O atoms, doing more stable on SiO2(001). The stability depends on the H-bonds formed and this is conformity with the highersilanol density of SiO2(001) surface. The stability of ampicillin on SiO2(111) is favored when the surface is amino functionalized and the major adsorption energy is observed in presence of the deprotonated specie at asic pH. The changes are mainly related to the modifcation on HOMO-LUMO distribution comparing with the neutral specie and in consequence, the new interactions with the amino functionalized surface that contribute with new states in the DOS Fermi region.