Graphene oxide-silver nanoparticles (GO-AgNPs) for antimicrobial applications and ecotoxicity

• Grant number: 24/18413-4
• Support Opportunities: Scholarships in Brazil - Program to Stimulate Scientific Vocations
• Start date: February 10, 2025
• End date: March 24, 2025
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Diego Stéfani Teodoro Martinez
• Grantee: Gabrielle Aguiar Dantas
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil

Abstract

Graphene oxide (GO) is an emerging nanomaterial, highly regarded for its properties and characteristics, such as hydrophilicity and reactivity. The existence of functional groups on GO's surfaces, such as carboxyl and carbonyl, improve the interactions with biomolecules and microorganisms, causing an antimicrobial effect by different mechanisms. Additionally, these oxygen groups allow the functionalization of GO with inorganic nanoparticles through several routes, which are associated with the improvement of materials properties. One of the most promising combinations is GO and silver nanoparticles (i.e. GO-AgNPs), which significantly enhance the antimicrobial activity, making the nanocomposite particularly attractive for biomedical applications.Another approach to improve the interaction between GO-AgNPs and microorganisms is the modification with sodium hypochlorite. This reaction is characterized by breaking the C-C bonds on the graphene basal plane by the strong oxidation by ClO-, which decreases the GO lateral size and modified its surfaces and properties, transforming into a different material that can be applied in a wide range of areas.This modification enhances the effects of smaller particles that can interact by many mechanisms.Safe-by-Design (SbD) is an emerging concept towards green chemistry practices and sustainability during the development of advanced materials. SbD can be employed to ensure their safety production, use, and disposal, referring to the identification of the risks and uncertainties linked to them. These strategies applied in nanotechnology provide the development nanoparticles (NPs) with design out of hazards, contributing to decrease their bio-persistence and harmful effects. The ecotoxicity assessment of GO-AgNPs is crucial to the development of safety materials with potential application. The effects are dependent on the physicochemical properties, size, oxidation degree and functionalization. Daphnia similis is an excellent alternative to evaluate the toxicity effects of GO-AgNPs due to being considered a model to water quality, and even low changes in the medium can indicate different effects. In this project, we will prepare and characterize GO-AgNPs materials for antimicrobial applications and ecotoxicity assessment.