Synthesis and bioactivity assessment of high silica content quaternary glasses with Ca: P ratios of 1.5 and 1.67, made by a rapid sol-gel process

J Biomed Mater Res A. 2018 Feb;106(2):510-520. doi: 10.1002/jbm.a.36239. Epub 2017 Oct 30.

Abstract

Sol-gel glasses in quaternary silica-sodium-calcium-phosphorous systems have been synthesized using a rotary evaporator for rapid drying without ageing. This novel fast drying method drastically decreases the total drying and ageing time from several weeks to only 1 hour, thus overcoming a serious drawback in sol-gel preparation procedures for bioglasses. This work investigates the bioactivity behavior of two glasses synthesized by this fast method, with Ca:P ratios of 1.5, and 1.67. X-ray diffraction (XRD), Inductive coupled plasma, Fourier-transform infrared, and Raman spectroscopy were used to confirm the bioactivity of the synthesized powders. MAS-NMR was also used to assess the degree of silica polymerization. The composition with a higher Ca:P = 1.67 ratio showed better bioactivity in comparison to the one with Ca:P = 1.5, which exhibited little bio-response with up to 4 weeks of immersion in SBF (simulated body fluid). It was also found that an orbital agitation rate of 120 rpm favors the interfacial bio-mineralization reactions, promoting the formation of a crystalline hydroxyapatite (HAp) layer at the surface of the (Ca:P = 1.67) composition after 2 weeks immersion in SBF. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 510-520, 2018.

Keywords: bioactivity; crystallization; glass; glass-ceramics; hydroxyapatite.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biocompatible Materials / chemical synthesis*
  • Biocompatible Materials / chemistry*
  • Calcium / analysis*
  • Glass / chemistry*
  • Hydrogen-Ion Concentration
  • Phase Transition*
  • Phosphorus / analysis*
  • Powders
  • Proton Magnetic Resonance Spectroscopy
  • Silicon Dioxide / chemistry*
  • Spectroscopy, Fourier Transform Infrared
  • Spectrum Analysis, Raman
  • Temperature
  • X-Ray Diffraction

Substances

  • Biocompatible Materials
  • Powders
  • Phosphorus
  • Silicon Dioxide
  • Calcium