Antibacterial activity of SiO2/hydroxypropyl cellulose hybrid materials containing silver nanoparticles

Silica hybrid materials containing tetraethyl orthosilicate (TEOS) as SiO₂ precursor, hydroxypropyl cellulose (HPC) as an organic compound with incorporation of silver were prepared, and their structure and surface morphology were examined by FTIR measurements and SEM. The quantity of organic substance was 5 wt.% and the silver concentration varied from 0.5 to 2.5 wt.%. It is suggested that the main structural units build an amorphous network of synthesized hybrids from depolymerized [SiO₄] tetrahedra giving strong bands at 1050 and 790 cm^? 1. The surface morphology changed from smooth to rough with the increasing amount of silver. The possible antibacterial behavior of the hybrid materials was also studied. The results indicate pronounced antibacterial performance against Escherichia coli and Bacillus subtilis. Highest antibacterial activity was detected against B. subtilis. The increase of silver concentration up to 2.5 wt.% Ag leads to stronger antibacterial effects with both strains.