Mechanical and In Vitro Bioactivity Study of Barium-based Bioactive Glass/Starch Nanobiocomposite as Candidate Graft Material for Bone Repair

E.R. Essien, V.N. Atasie, K. Tekelu, J.O. Kekene, L.A. Adams
University of Lagos,

Keywords: bioactivity, starch biocomposite, barium-based bioactive glass, hydroxyapatite, degradability


Bioactive glass/polymers composite as implants induce bone bonding and congruent degradability without eliciting adverse immunological responses. Low economy strategies are needed to provide affordable bone intervention materials for low economy countries. Herein, we investigated the compressive strength and bioactivity of a barium-containing bioactive glass/starch composite, wherein the quaternary glass consisted of SiO2-CaO-BaO-P2O5. The bioactive glass was prepared by solution precipitation from sodium metasilicate (Na2SiO3.9H2O) as a low-cost silica substitute to alkoxysilane precursors and used as a filler phase in a starch-based matrix. The obtained composite was characterized to evaluate the compressive strength, morphology, phase composition, particle size, and bond properties using a mechanical tester, SEM-EDX, XRD, TEM and FTIR respectively. Bioactivity was assessed on the ability of the samples to induce hydroxyapatite (HA) on their surfaces in Simulated body fluid (SBF) for 7 – 14 days. Results obtained showed that the bioactive glass composite exhibited superior compressive strength, morphology, bioactivity and degradability compared with the pristine samples. The compressive strength increased significantly from 2.42 ± 0.31 MPa in the neat bioactive glass to 6.59 ± 1.01 MPa in the bioactive composite. The particles (average size: 33.94 ± 10.71 nm) of the bioactive glass composite gave a better distribution compared to the pristine glass (average size: 52.69 ± 8.63 nm). Furthermore, the diffractogram of the bioactive glass composite gave higher HA peaks after soaking in SBF for 7 days, and after 14 days, the crystalline silicate peaks transformed to amorphous phase. We report a barium-based bioactive glass composite with desirable properties which can, therefore, be considered as a promising graft material for bone repair.