Molecular dynamics simulations of bio-active phosphate-based glass surfaces

Article history: Received 2 February 2016 Received in revised form 24 May 2016 Accepted 5 June 2016 Available online 11 June 2016 Classical molecular dynamics (MD) simulations were used to study the structural changes in the surfaces of biocompatible phosphate glasseswith compositions (P2O5)0.45(CaO)x(Na2O)0.55−x (x=30, 35, 40) to evaluate their effect on the solubility of the material. Direct comparison of the data for the three compositions highlighted the critical role that an enhancement in Na concentration plays in the hydrolysis of the material, which is responsible for the release of network components into solution. The calculations also confirm that themost solublematerial is (P2O5)0.45(CaO)0.30(Na2O)0.25, has the lowest calcium coordination number, thereby causing fewer cross links to phosphate chains. © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).