Antimicrobial activity of CeO2 nanoparticles in vitro on Escherichia coli and Staphylococcus aureus bacteria

• Grant number: 13/22244-9
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2014
• Effective date (End): July 31, 2015
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Alexandre Zirpoli Simões
• Grantee: Jacqueline Stella Barbosa de Souza
• Home Institution: Faculdade de Engenharia (FEG). Universidade Estadual Paulista (UNESP). Campus de Guaratinguetá. Guaratinguetá , SP, Brazil
• Associated research grant: 13/07296-2 - CDMF - Center for the Development of Functional Materials, AP.CEPID

Abstract

Large efforts in engineering nanostructures has increased in recent years due to their use in energy and biomedicine. To ensure the development of these nanomaterials, the effects of these structures on the environment must be understood. The interactions of nanomaterials with microorganisms are inevitable, but overall consequences of such interactions are unknown due to the lack of standardized methods for evaluation. Therefore, the main goal of this project is to obtain cerium oxide nanoparticles synthesized by the hydrothermal microwave assisted technique evaluating the interactions of these nanoparticles on the growth of the Staphylococcus aureus and Escherichia coli species. Such interactions are monitored as a function of particle size, growth medium, pH, surfactant, and minimum inhibitory concentration. One approach of hydrothermal synthesis will be used to prepare cerium oxide nanoparticles in various particle sizes in order to eliminate complications coming from the use of organic solvents. Multiple analytical approaches will be employed for evaluation of toxicity and different bacterial systems highlighting its potential interactions with nanomaterials at room temperature. This proposal aims to investigate the bactericidal properties of CeO2 crystals synthesized from aqueous solutions of cerium salts processed in the hydrothermal system assisted by microwave radiation. The obtained crystals will be characterized by: X -ray diffraction, vibrational spectroscopy in the infrared region, field emission gun scanning electron microscopy (FEG-SEM, transmission electron microscopy (TEM) , optical emission spectrometry with inductively coupled plasma (ICP - OES). It will be evaluate the antimicrobial activity of CeO2 crystals to combat two types of bacterias: Staphylococcus aureus and Escherichia coli. (AU)