Cellulose-Silver-Graphene Nanocomposites in the Tropical Environment: Biodegradation, Structural Characterization and Ecotoxicity Assessment

• Grant number: 24/16474-6
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: July 01, 2025
• End date: June 30, 2028
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Diego Stéfani Teodoro Martinez
• Grantee: Francisco Lucas Chaves Almeida
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Associated research grant: 21/11967-6 - Center of Sciences for the Development CCD - Solutions for post-consumer waste: packaging and products, AP.CCD

Abstract

The replacement of plastic by biodegradable films has been widely studied, as plastic materials take a long time to degrade increasing environmental pollution. Nanocellulose films both containing or not additives (i.e., silver nanoparticles and graphene oxide) show interesting properties to produce new advanced materials as a plastic substitute. However, the biodegradation process and its effect on the soil and aquatic ecosystems is still unknown, mainly in the tropical environment, since no study has been reported on this topic even considering the relevance of physico-chemical and biological transformations in the environment. This project aims to investigate the biodegradation of cellulose-silver-graphene nanocomposites (films) in a Brazilian tropical environment (i.e., soil and water systems) under both aerobic and anaerobic conditions linked to their ecotoxicological effects on microorganisms, enzymes, and aquatic organisms. To achieve that, the project is divided into six work plans: (i) Production and characterization of materials; (ii) Morphological and chemical characterization of materials after biodegradation; (iii) Soil and water biotransformation, enzymes and microbial responses; (iv) Aquatic ecotoxicity assessment, and (v) Prospective life cycle assessment of cellulose-silver-graphene nanocomposites and (vi) FAIR data towards safe-by-design, harmonization, and regulation. In each of these work plans, integrated analytical techniques will be used to understand the (bio)degradation process and its impact on the nanocomposites. Moreover, enzymatic analysis, microorganism counting, microbial metabolism, and aquatic toxicity using Daphnia as a model will also be assessed. All data generated in this project will be treated following the NanoCommons KB protocols and CompSafeNano and INSIGHT ongoing projects, contributing to the establishment of harmonized data acquisition practices in nanosafety research through Brazil-Europe cooperation. We expect to advance the understanding of material-bio-ecological interactions, taking crucial steps to decipher the phenomena that evolves cellulose-silver-graphene nanocomposites biodegradation in tropical environment for the first time; accessing changes on toxic responses through due material transformations, and advancing in this highly relevant subject for nanotechnology and advanced materials in Brazil. Finally, correlating its interfaces with safety and regulation, we move towards a sustainable innovation approach in material science and technology. (AU)