Mesoporous electroactive silver doped calcium borosilicates: Structural, antibacterial and myogenic potential relationship of improved bio-ceramics

In this work improved electroactive mesoporous Ag-doped bio-ceramics for medical usages are developed, examining their structural, electrical, in-vitro bioactivity, cell cultures and antibacterial properties against various classical pathogenic bacteria. Ag-containing mesoporous bio-ceramics (MBCs): xmol%Ag2O (100-x) [45.8CaO-8.4B(2)O(3)-45.8SiO(2)] where x = 2, 5, 7.5 and 10 were synthesized through a sol-gel method. The small angle X-ray scattering and electron microscopy studies reveal the embedment of silver nanoparticles in the samples. Existence of silver as Ag+/Ag-0 forms in the samples is confirmed by X-ray photoelectron spectroscopy. The N-2 adsorption-desorption analysis evidence the mesoporous structure of the samples. The electrical conductivity of samples increases from 5.4 x 10(-8) S cm(-1) for x = 2 to 1.9 x 10(-6) S cm(-1) for x = 7.5 and then decreases to 0.9 x 10(-6) S cm(-1)u for x = 10 at 110 degrees C. In vitro bioactivity studies revealed that Ag-containing MBCs hold the bone-like hydroxyapatite formation after immersion in human blood plasma like-solution such as Dulbecco's Modified Eagle's Medium. The antibacterial effect of samples against pathogenic bacteria (S. aureus, E. coli, P. monas aeruginosa, and B. cereus) increases with Ag concentration (x = 7.5) and then decreases with Ag content (x = 10). Antibacterial effect is greater for the sample with high electrical conductivity. The cell culture studies evidence not considerable cytotoxic effects for Ag-containing MBCs. Finally, the C2C12 myoblast cell culture studies reveal the significant cell growths and differentiation (myogenesis) for high electrical conducting Ag-containing MBCs.

Automated summary

Improved electroactive mesoporous Ag-doped bio-ceramics were developed for medical purposes, showing varying antibacterial effects and electrical conductivity depending on silver concentrations.