INTERAÇÃO DE MOLÉCULAS AROMÁTICAS EM GRAFENO PURO E FUNCIONALIZADO VIA SIMULAÇÃO COMPUTACIONAL

• Autor(a) principal: Tonel, Mariana Zancan
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional Universidade Franciscana
• Texto Completo: http://www.tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/704
• topic: Interação, funcionalização, grafeno, DFT, entrega de fármacos, remoção de poluentes, parametrização de campo de força; Drug delivery, DFT, Force field parameterization, functionalization, graphene, interaction, removal of pollutants; Nanociências

Graphene is a nanomaterial that has several applications including drug delivery and pollutant remover. However, graphene is hydrophobic, which makes it difficult to apply in biological media, and one of the alternatives is through functionalization. At the same time, aromatic molecules are precursors of several essential compounds for life, and are also important in industry. However, some of them are pollutants that can severely affect people and the environment, so developing effective removal methods is extremely interesting. Some molecules of biological interest like dopamine and serotonin have an aromatic part, recent studies show the use of these molecules as mediators for specific and selective drug delivery. Therefore, the study of the interaction of these molecules as pure and modified graphene is of great importance in the biomedical area as well as for diagnostic and treatment studies. In this work, we perform a theoretical study through the density functional theory; initially we analyze the changes caused by the effect of the concentration of the functional groups -COOH, -COH, -OH, -O- or -NH2 on graphene. The results show that in all cases it is possible to modulate the electronic properties depending on the number and location of the groups. Subsequently, we analyzed the graphene pure and functionalized with a group -COOH, -COH, -OH, -O- or -NH2, with the molecules of biological interest as dopamine, serotonin and the pollutants: benzene, aniline, benzoic acid and phenol. The results show that all interactions occur under a physical adsorption regime, there are no changes in the original geometric structures of the molecules after adsorption, it may be of interest to create possible routes as mediators for the delivery of drugs and to assist in the treatment of various diseases or in a system of removal of pollutants based on pristine and modified graphene. Finally, we developed a method to parameterize the benzene-benzene and benzene-graphene force field through the data obtained from the ab initio calculations, the results obtained agree with studies described in the literature. Thus, this work presents the understanding through the simulation of the biomedical part for drug delivery systems, and removal of pollutants, in addition to the parameterization to be used in simulations of the biological environment which may aid in the development of future experimental studies.