Surface microstructure and chemistry of functionalised Bioglass-derived glass-ceramics

Cell attachment onto Bioglass-derived glass-ceramics can be improved through surface chemical treatment, such as silanisation using aminopopyl-triethoxysilane (APTS). One concern raised by this treatment is that the alkalinity of the silane could change the surface topography such that attached cells might eventually be negatively affected by the sharp ridges formed during silanisation. It is, therefore, necessary to find out an optimal treatment condition at which a monolayer of APTS forms on the glass-ceramic surface without leading to sharp features on the surface. In this work, Bioglass-derived glass-ceramics pellets were treated in an APTS solution at 80°C for 1, 2, 3, and 4 h, immediately followed by microstructural and compositional analysis. It was found that the glass matrix dissolved and crystalline particles were leached out during the surface treatment, leaving a honeycomb-like morphology on the surface. One hour treatment was sufficient for the attachment of APTS molecules, and further treatment did not increase APTS amount considerably, while sharpening the surface topography remarkably.