Structural and surface studies on calcium phospho-silicate glass-ceramics containing zinc and iron oxide

Effects of ZnO addition on structural and microstructural properties of glass/glass-ceramic with nominal composition 25SiO(2)-50CaO-15P(2)O(5)-(10 - x) Fe2O3 - x ZnO (where x = 0-5 mol%) have been studied. Glasses were prepared by melt-quench technique and converted into glass-ceramics by controlled heat treatment. The glass-ceramics samples were immersed in bovine serum albumin (BSA) and their surfaces were investigated using Fourier transform infrared spectroscopy (FTIR) and time of flight-secondary ion mass spectrometry (TOF-SIMS). Microstructure of glass-ceramic exhibited a granular microstructure. Calcium phosphate, calcium silicate (Ca3Si2O7), hematite and magnetite phases were observed. Surface morphology of glass-ceramics after immersion in BSA showed the formation of Si-OH functional groups. Absorption of BSA took place by interacting with the silanol groups present at the surface. The fraction of non-bridging oxygen decreased with the increase in the amount of ZnO, which led to a decrease in the surface dissolution; thereby decreasing the adhesion of BSA (c) 2013 Elsevier B.V. All rights reserved.