Fabrication and characterization of porous 3D TCP-CMC- alginate fibrous constructs for implant applications

This study reports the fabrication of 3D constructs using Tri-calcium phosphate/carboxymethyl cellulose composite with alginate. Microporous scaffold fibers were developed by incorporating gas bubbles within fibers, stabilizing it with surfactants, and subsequently removing the gas by vacuum treatment. The prepared paste was dispensed through a specially designed sieve plate by applying pressure and extruded in a calcium chloride/acetic acid bath. Gas is evolved as a result of reaction between sodium bicarbonate in paste and acetic acid in solution. The porosity of the fiber is tuned using 0.9, 1.8 and 3.6 weight% sodium bicarbonate (NaHCO3). Fibers were characterized using scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP). The morphology of the scaffold was characterized using scanning electron microscopy (SEM). Pore morphology was found to be better in scaffolds with 0.9 wt% NaHCO3 as it revealed an interconnected structure. MIP results showed an increase in pore volume with increasing concentration of NaHCO3. Study on the mechanical properties of the constructs was carried out to evaluate the compressive strength. In-vitro bioactivity studies were carried out in simulated body fluid (SBF) for 2/4 weeks. The study showed that the scaffold provides favorable substrate conditions to form bone like mineral HA phase, which plays a significant role in osteointegration