Microbicidal action in natural and synthetic fabrics promoted by phenothiazines

Microbicidal action in natural and synthetic fabrics promoted by phenothiazines

• Autor
• Lilian Martins-Nascimento
• Co-autores
• Carin Cristina S. Batista , Juliana D. Bronzato , Martha T. Oliveira , Silgia Aparecida Costa , Sirlene Maria da Costa , Otaciro Rangel Nascimento , Karina Frin , Iseli Lourenço Nantes
• Resumo

• The advent of the COVID-19 pandemic and resistant bacteria strains have led to growing interest in self-disinfecting materials. One interesting strategy against pathogenic microorganisms is the functionalization of fabrics used in PPEs with antimicrobial agents. The modification of fabrics with nanoparticles and molecules generating pro-oxidant species could combat simultaneously virus and bacteria by attacking their structural biomolecules. In the present study, for the first time, it was demonstrated that natural and synthetic fabrics could gain microbicidal properties after the impregnation with photogenerated radical cations of 10H-phenothiazine (PHT) and fluphenazine (FP) by Type I mechanism. Cotton fabric dyed by Sulphur black, obtained by successive sulfurization of phenothiazine derivatives was also converted to radical cation when exposed to room illumination. Sulphur black, PHT and FP radical cations generated by Type I mechanism were characterized by EPR. Oxidative attack of the dyes on virus envelope and bacteria membranes were evidenced by the quenching of EPR signal of fabrics exposed to a membrane model and by cryo-TEM (cryo-Transmission Electron Microscopy) images. The steady state monomol photoemission of singlet oxygen at 1270 nm was not detected for FP and Sulphur black indicating that the microbicidal action comes exclusively from the free radical attacks. PHT exhibited a low intensity singlet oxygen emission at 1270 nm indicating that Type II mechanism could partially contribute for the microbicidal action. For the first time it is demonstrated that photochemical Type I and II mechanisms of photosensitizers can provide microbicidal properties in fabrics. One advantage of the pro-oxidant attack is the non-specificity that allows efficiency against different viruses and bacteria.

  This work was supported by FAPESP 2017/02317-2 and CNPq 313111/2021-9 (ILN) and CAPES 88887.513142/2020-00.

• Palavras-chave
• Microbicidal action; cotton fabrics; facial masks; phenothiazines.
• Modalidade
• Pôster
• Área Temática
• Materiais Funcionais Avançados