Dissolution studies of Na2O-BaO-CaO-P2O5 glasses in deionized water under semi-dynamic conditions for bioactive applications

Abstract

The phosphate glasses of composition Na<inf>2</inf>O-CaO-P<inf>2</inf>O<inf>5</inf> are widely accepted glass material for biomedical applications. The glass samples with composition (26-x)Na<inf>2</inf>O-xBaO-29CaO-45P<inf>2</inf>O<inf>5</inf> (x = 0,5,10,15) are prepared at 1100°C by melt-quenching technique. In order to reduce the fast dissolution rate, which limits their application, BaO is added by reducing Na<inf>2</inf>O composition. The dissolution studies have been carried out in deionized water under semi-dynamic conditions at 37°C for 14 days. The properties are studied based on Barium composition and time of immersion. The samples are taken out at 24 hrs. intervals to carry out weight loss and pH measurements. The rates of cation (Na+ and Ca2+) release from the glass to the solution were found out using flame photometer. The release of orthophosphate (PO<inf>4</inf>3-) anions is measured by UV-Visible spectrometer using phospho-molybdenum blue method. The weight losses linearly increase with time for all the compositions. The addition of barium decreases the weight loss in deionized water. The pH of the solutions varies with dissolution of ions. The dissolution rate has been found out from the slope of the weight loss vs time graph and it decreased with increase in barium content. © 2018 Elsevier Ltd. All rights reserved.