Synthesis of hydrogel bio-composite based on biphasic calcium phosphates nanoparticles, oxidized alginate and gelatin for bone regeneration

Abstract

Composite hydrogel materials consisting of oxidized alginate, gelatin, and biphasic calcium phosphate in which polymeric network was fabricated via a Schiff-base reaction. The effect of BCP weight ratio on the material properties, and biocompatibility were evaluated. Alginate was modified by oxidizing vicinal hydroxyl groups to two CHO groups that can react with abundant -NH2 groups of gelatin. The hydrogel structure was highly porous and interconnected with pore diameters ranged from 200 to 500 mm. BCP nanoparticles (mixture of hydroxyapatite and tricalcium phosphate) were prepared by precipitation method under ultrasonic irradiation using calcium chloride and di-sodium hydrogen phosphate. The BCP nanoparticles were characterized by using X-ray powder diffraction (XRD), scanning electron microscopy (SEM). The synthesized BCP-NPs, with their variety in weight ratio on the hydrogel, contributed great impact on the decomposition of calcium phosphate layer on the surface of the scaffold throughout incubation in simulated body fluid (SBF) buffer solution. The hydrogel composite were biodegradable and highly bio-biocompatible. Biomineralization study indicated the formation of apatite layer onto the composite surface after 2 weeks soaking in simulated body fluid (SBF) buffer solution. These obtained results exhibit a great potential of the hydrogel composite for bone regeneration. Keywords: Oxidized alginate Hydrogel Gelatin Biphasic calcium phosphate