Arnab Mahato
CSIR-Central Glass and Ceramic Research Institute, India
Title: Development of nano-porous hydroxyapatite coated e-glass for potential bone-tissue engineering application: An in vitro approach
Biography
Biography: Arnab Mahato
Abstract
Large segmental defects resulting from trauma, surgical excision or cranioplasty have complex 3D structural needs which are difficult to restore. To overcome these concerns several alloplastic materials including metals, plastic, ceramics and composites are used for the reconstruction of skull bone defects with limited success. To overcome the problems, a biocompatible and osteo-conductive FRC (fiber reinforced composite) implant using e-glass as a base has been proposed. As a first step of this process, nano-porous hydroxyapatite (HAp) was coated on e-glass substrate which obviates leaching of base glass network former/modifier and bio-inertness on surface and necessitates bone bonding/soft tissue bonding at the surface to functionally restore at implanted site. In a nutshell, Ca-P sol was synthesized and applied on inert e-glass substrate by freeze-drying method and after calcination (850-950o C), nano-porous HAp coating was developed. After thorough material characterization including XRD, FTIR, Raman, FESEM, TEM, MTT assay and nano-mechanical tests, the composite was tested for in vitro static and quasi-dynamic bioactivity in contact with SBF (simulated body fluid) up to 7 and 14 days at 37.4o C. Same set of characterizing parameters were studied subsequently. It was found that non-cytotoxic crystalline HAp with ~10 μm coating thickness and fairly high bonding strength was obtained on the substrate with pores around 300-500 nm throughout and with cellular like microstructure on the surface of e-glass which was again very suitable for tissue in-growth and bone-bonding ability. For as-prepared coated substrates, TEM results revealed graded amorphicity from substrate to periphery and deposition of flaky Ca-P crystals after 14 days of both static and quasi-dynamic SBF bioactivity study. Nano-indentation at 1 mN load showed significant increase of hardness after SBF study. Cell viability test through MTT assay using fibroblast (L-929) and osteoblast (MG-63, osteosarcoma) cell-line showed non-toxicity of the composite. SEM image after cytotoxicity test showed enormous cell-proliferation on the surface of the samples after 7 days. These results thus showed a very promising application as a new biomaterial for repair and reconstruction by bone tissue engineering application.