Silver doped silica-methyl hybrid coatings. Structural evolution and antibacterial properties.

R.A. PROCACCINI; C. STUDDERT; S.A. PELLICE

SURFACE AND COATINGS TECHNOLOGY

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2014 vol. 244 p. 92 - 97

0257-8972

In this work, the effect of silver doping on the organic-inorganic hybrid structure of sol-gel coatings and its performance as bactericidal materials was analyzed. Coatings were synthesized through the hydrolytic condensation of tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES); silver nitrate was used as a source of Ag+ ions. The structural analysis, performed through Small Angle X-ray Scattering (SAXS) with synchrotron light, Fourier Transformed Infrared (FTIR) and UV-visible spectroscopies, revealed the complex scenario developed as the network crosslinking rises during the thermal treatment. The matrix structure works as a size-selective membrane where only the smaller silver clusters and ions are released to the surface while the higher nanoparticles remain trapped inside. Finally, bacteriologic analysis, performed with E.coli cultures, confirmed a tight correlation between silver lixiviation and the inhibition halos observed in agar diffusion tests.