Development of Bactericidal Biotechnological Prototypes for the Efficient Disinfection of Sanitary Effluents

Bacterial cellulose (BC) has high thermal/mechanical stability, but its hydrophilicity limits applications. In this work, BC was modified with silica for antimicrobial filtering. Membranes were treated with base/intercalator (5h), then immersed in tetraethyl orthosilicate (TEOS) ethanolic solution (24h). The material efficiently filtered Pseudomonas aeruginosa and Staphylococcus aureus (10⁸, 10⁷, 10⁶ cells/mL). In the infrared spectrum of the silica-modified BC, it was possible to observe a symmetric stretching at 794 cm^-1 related to Si-O-Si bonds, as well as the disappearance of the strong and broad band at 3410 cm^-1 attributed to O-H stretching, which is present in the unmodified membrane. Using Scanning Electron Microscopy, spherical silica particles were observed on the TEOS-modified membranes. Therefore, using BC as a prototype with bactericidal activity represents an innovative approach to deploying ecologically efficient filters.