Desenvolvimento de novas tecnologias baseadas em materiais biocidas

Abstract

The worldwide outbreak of the coronavirus pandemic (COVID-19) and other emerging microbial infections have attracted particular interest in the design and development of new biocidal agents with a broad spectrum of activity. Since then, efficient strategies need to be implemented for the rapid diagnosis, prevention, control and treatment of the SARS-CoV-2 virus, its variants, and other opportunistic pathogens. In the current scenario of SARS-CoV-2 infections, the technological challenge lies in the development of economically viable biocidal systems, reusable and capable of inactivating opportunistic pathogens, thus reducing the risk of infection and transmission. In this sense, Ag-based materials used in small quantities can become attractive for the development of new biocidal technologies. α-Ag2WO4, which already shows biocidal activity, when modified by electrons or femtosecond laser increases its biocidal activity up to 32x, against resistant bacteria (methicillin-resistant Staphylococcus aureus) and fungi (Candida albicans) due to the generated metal-semiconductor interface (Ag/α-Ag2WO4). In addition, this modification makes this interface selective for combating bladder cancer cells (MB49), versus healthy cells (BALB/3T3), using model mouse cells. Ag/SiO2 immobilized on ethylene vinyl acetate (EVA) was another studied interface which showed 99.99% inhibition of bacteria (Staphylococcus aureus and Escherichia coli) and fungi (Candida albicans), besides eliminating in just 2 minutes over 99% of SARS-CoV-2 virus replicates. In this way, safe biocidal technologies can be obtained using silver-based metal-semiconductor interfaces, which can be applied to the design of personal protective equipment (PPE), packaging, fabrics, hygienic implements such as implants and prostheses, and other devices economically feasible to combat the increase in pandemics and fatal risks associated with various pathogens.