Structural, physico-mechanical and in-vitro bioactivity studies on SiO2-CaO-P2O5-SrO-Al2O3 bioactive glasses.

Strontium based bioactive glasses have shown a better biocompatibility than calcia based bioactive glasses. In this report, we have shown that the bioactivity is found to be even more when we incorporate Al2O3 upto 1.5 mol% in SiO2-CaO-P2O5-SrO bioactive glass. We have studied the structural, physico-mechanical and bioactive properties in these glasses with varying alumina concentration from 0.5 to 2.5 mol%. The bioactivity of the glasses is evaluated by in vitro test in simulated body fluid (SBF). The formation of hydroxy carbonated apatite layer (HCA) on the surface of glasses after immersion in SBF is identified by the XRD, FTIR and SEM. The substitution of Al2O3 for SrO in these glasses demonstrates a significant enhancement in compressive strength and elastic modulus. However cytotoxicity and cell viability assessed using human osteosarcoma U2-OS cell lines show the growth of the cells without causing any significant loss of viability and cell death upto 1.5 mol% addition of Al2O3. Osteosarcoma cells grow on the surface of bioglasses which make them biocompatible and fit for use in clinical trials.

Pharmacological application of barium containing bioactive glass in gastro-duodenal ulcers.

Peptic ulcer is prevalent in about 4% of the world population and nearly 10% of people have been affected by peptic ulcer at some point in their life. Therefore, there is a need for newer efficient and safe anti-ulcer agents. In the present strategy, we have prepared a novel bioactive glass containing 1.3 mol% of barium oxide (BaBG) and evaluated its antiulcer potential in gastroduodenal ulcer models. Prophylactic effect of BaBG pretreatment was evaluated for 5 days in ethanol, aspirin and pyloric ligation-induced gastric ulcer and cysteamine-induced duodenal ulcer models. Repeated treatment of 10 days of BaBG was evaluated in the healing ulcer model of acetic acid. BaBG significantly reduced the ulcerative damage against all the five tested ulcer models. Scanning electron microscope (SEM) images have shown that BaBG forms a physical protective barrier over the gastro-duodenal epithelium cell. In the pyloric-ligation, ethanol and aspirin models, BaBG showed significantly increased in gastric pH, indicating antacid like activity. BaBG treatment significantly increased cell proliferation in the pyloric model. Thus, BaBG mediates antiulcer action by forming a protective physical barrier against harsh luminal factors, acid neutralization and cell proliferation.