Antibacterial and structural properties of mesoporous Ag doped calcium borosilicate glass-ceramics synthesized via a sol-gel route

Structural, electrical, bioactivity and antibacterial properties of mesoporous Ag doped calcium borosilicate glass ceramics are reported. A simple sol-gel route was used to synthesize the mesoporous glass-ceramics. N-2 adsorption-desorption studies reveal the mesoporous structure of the samples. The embedment of nano-sized Ag metallic particles in glass matrix was confirmed for Ag doped sample calcined at 600 degrees C by X-ray diffraction, UV-visible, and transmission electron microscopic analyses. Ac conductivity is used to study the electrical relaxation processes. Ag nanoparticle-embedded sample reveal nearly constant loss behaviour, whereas silver ions alone embedded sample show universal dielectric relaxation behaviour. Ag doped samples exhibit good antibacterial properties without compromising the bone-like apatite layer formation. The antibacterial effect against Gram negative bacteria is higher for Ag doped sample calcined at 600 degrees C which exhibits a dominant nearly constant dielectric loss feature.