Biomaterials with antibacterial activity

The sol-gel derived silica spheres with surfaces modified by silver nanoparticles were used to enhance the photodynamic effect. The silica nanoparticles were prepared by modified Stöber synthesis. The diameter of obtained silica spheres was ca. 100 nm. These silica spheres we used as a carrier for noble nanoparticles. It was shown that Ag-Au nanoparticles have an antibacterial activity against Escherichia coli. This effect depends on the nanoparticles concentration and it is stronger for higher concentrations. Laser irradiation enhances this effect, and starting from certain concentration it is possible to kill Escherichia coli, totally, when using laser light