Silica materials with biocidal activity

Pathogenic microorganisms like fungi, bacteria and algae are harmful to human beings and animals. Moreover, they contribute to the destruction of building materials by their biodegradation. Therefore, they create serious hazard for the natural environment. To prevent these phenomena, different materials with biocidal activity are being developed. In elaboration of such materials, one of the most difficult problems to be solved is the achievement of their high effectiveness in controlling harmful microorganism population with the guarantee of safety of their application to the natural environment and humans. As a result of investigation carried out in the INCT on new biocides based on quaternary N-alkylammonium salts (QAC), mainly benzalkonium chloride, and water glass (WG) large group of new silica materials with biocidal activity were synthesised. Possibilities of technology modification in order to obtain different profitable properties of materials are presented in the paper. Preliminary investigations concerning biocidal activity against selected mould fungi, bacteria and algae were performed. Results of microbiological investigations proved stable effectiveness of biocides for protection from harmful microorganisms growth, which does not decrease even after washing of biocidal material with water. Silica materials with biocidal activity due to structural binding of biocidal agent (QAC) can be applied in building industry as materials of high ecological safety.