Evaluation Of 3d Bio-Printed N,O Carboxymethyl Chitosan And Oxidized Xanthan Gum Scaffold Incorporating Biphasic Calcium Phosphate

Abstract

In the context of bone defect in Vietnam, the advent of artificial bone grafting surgery has contributed to changing lives of many patients but still pose risks and remain high cost method. Lately, 3D printing is being widely used for manufacturing the alike 3D structure as the targeted tissue by various types of biomaterials with the purpose of bring a better effectiveness for regeneration. Among that, extrusion based 3D bioprinting is the most versatile, fast, scalable, and cost effective technique. In this study, NOCC, OXG and BCP will be chosen to fabricate the bioink for 3D printed scaffold fabrication by overcome the limitation of low mechanical strength of natural hydrogel and enhance the osteoconductive property for better new bone growth. NOCC/OXG/BCP hydrogel, forming crosslinks by Schiff base reaction without requiring any chemical linkers or radial light sources, offers a porous scaffold and enhancing the osteoconductivity by the ceramic component. Chitosan and xanthan gum with different oxidations levels are structurally modified and confirmed via FTIR. By high mechanical strength at up to 80 kPa, average pore size at about 200 to 300 um, BCP content of 50, 60, and 70% incorporated into the hydrogel system were chosen for further experiment. With infill 35%, printing speed at 650 mm/min, pressure from 2 to 3MPa, G22 nozzle were considered as successful for print the 3D scaffold with area 1x1x1 cm3. Porosity, swelling degree, and degradation rate revealed the significant effect of BCP particle incorporation into the hydrogel system when compared to NOCC-OXG sample. Furthermore, in vitro testing showed the biocompatibility and bioactive of cells culturing with 3D printed scaffold; with the support for cell attachment on surface of the scaffold when compared to BCP-free hydrogel as the control group.