Microbial biotemplates for obtaining silica porous carrier for antibacterial substance

This study proposes an alternative to the template method for forming porous silica carriers. Bacterial cells of Rhodococcus fascians VKM B-1462 and Pseudomonas veronii VKM B-877 were utilized as biotemplates for the synthesis of a material based on tetraethoxysilane and methyltriethoxysilane (50/50 vol. %). As comparison samples, type III and IV materials were synthesized using cetyltrimethylammonium bromide (CTAB) micelles as templates, using methyltriethoxysilane and tetraethoxysilane 50/50 vol.%, as well as 100 vol.% tetraethoxysilane. The templates were removed from the materials by high-temperature annealing in the range from 200 to 1200 °C. The formation of a silicon-containing matrix was confirmed by scanning electron microscopy and IR spectroscopy. The optimal temperature for the removal of templates from materials was determined to be 800 °C for all types of material. An antiseptic substance, octenidine dihydrochloride, was loaded onto silicon carriers. UV spectroscopy revealed that the matrix formed using the Rhodococcus fascians biotemplate demonstrated optimal sorption and desorption properties. In comparison with the CTAB template, the employment of microbial cells has the potential to offer a number of applications due to cost-effectiveness, environmental safety, and ease of removal of the pore-forming agent.