A cost effective SiO₂-CaO-Na₂O bio-glass derived from bio-waste resources for biomedical applications

The present paper describes the in vitro bioactivity, cytocompatibility and degradation performance of SiO₂-CaO-Na₂O bio-glass synthesized using bio-waste. Egg shells and rice husk ash (RHA) bio-wastes were used as sources of calcium oxide (CaO) and silica (SiO₂), respectively. Glass samples were obtained by melt-quenching technique. Bioactivity was studied using in vitro experiments in simulated body fluid (SBF), degradation behaviour was evaluated in Tris-HCl buffer solutions recommended by ISO 10993-14 standards and cytocompatibility was estimated using MTT assay. The formation of hydroxyapatite was characterized by XRD, FTIR and SEM-EDS after soaking the glass samples in SBF solution. XRD confirmed the phase of hydroxyapatite with its standard JCPDS data. FTIR analyses revealed the occurrence of distinctive functional groups related to hydroxyapatite. Surface micrographs showed the agglomerated globular shape morphology of hydroxyapatite, while EDS analysis confirmed the existence of biological elements of apatite such as Ca, P and O. Degradation study results showed that the glass thus prepared has considerable controlled degradation rate. MTT assay revealed the cytocompatibility nature for different dosages (1000-50 μg/mL) of the prepared glass with MG-63 cells. These results perfectly established that egg shells and RHA are potentially beneficial resources for the production of bio-glasses.