Desenvolvimento de um nanobiossensor para o monitoramento da qualidade ambiental no setor agrícola

• Ano de defesa: 2013
• Autor(a) principal: Bueno, Carolina de Castro
• Orientador(a): Leite, Fábio de Lima
• Banca de defesa: Etchegaray Junior, Augusto , Steffens, Clarice
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Carlos
• Programa de Pós-Graduação: Programa de Pós-Graduação em Ciência dos Materiais - PPGCM-So
• País: BR
• Palavras-chave em Português: biossensores; nanotecnologia; Microscopia de Força Atômica; nanobiossensor enzimático; detecção de agroquímicos, diclofop; agricultura
• Palavras-chave em Inglês: enzyme-based nanobiosensor; agrochemical detection; diclofop; Atomic Force Microscopy; agriculture; nanotechnology
• Área do conhecimento CNPq: OUTROS
• Link de acesso: https://repositorio.ufscar.br/handle/20.500.14289/1172

The elaboration of highly-sensitive and selective functional nanobiosensors has significant applications for purposes of resilience and conservation of natural resources, to contribute on projects aimed to pointing out degraded and contaminated areas (soil and water), as well as being a quality indicator. In the present work, a nanobiosensor has been developed based on the biomimicry of the action mechanism of the herbicides in plants coupled with the Atomic Force Microscopy (AFM) tools. To sense the herbicide molecule at very low concentrations, the technique of the sensor construction was based on chemical functionalization of the surfaces of the AFM probes and substrate in order to prioritize covalent bonds and to improve the molecules flexibility, as well as to achieve reproducibility and accurate results. The architecture and molecular design of the nanobiosensor were based on the molecular spatial arrangement, binding efficiency and localization, host-guest specificity, and its binding energies which were analyzed by Molecular Docking and Molecular Dynamics Simulation. The results were based on the adhesion force (carried out by force curves data) between the AFM probe functionalized with ACCase enzyme and the substrate functionalized with herbicides. The results indicate that the specific target molecule of agrochemical was efficient, when compared with others nonspecific agrochemicals. The difference between the values of specific recognition (diclofop) and nonspecific (imazaquin, metsulfuron and glyphosate) is, on average, 90%. This evidence validates the selectivity and specificity of the nanobiosensor. This work presents the first evidence of nanolevel detection of diclofop by AFM probes sensors.