a novel porous bone scaffold made with 3d bioprinter using carboxymethyl chitosan-hyaluronic acid for knee repair: mechanical and chemical properties

Porous bone scaffolds are made by various methods such as membrane lamination, space holder, freeze-drying, and 3d printing techniques. with the advent of 3d printing, this method has emerged as a new tool for designing porous scaffolds.  the porous scaffolds are expected to have a multifunctional effect and changing porosity patterns as an approach to integrating the mechanical properties of different designs into a unique scaffold design. the knees, as a large joint, in addition to helping the limbs, also bear the weight of the body. in this study, the bone scaffold was fabricated using materials such as carboxymethyl chitosan (cchi) and hyaluronic acid (hla) using a three-dimensional bioprinter method for repairing the knee joint bone. in this study, scanning electron microscopy (sem) analysis is used to study morphology.  in order to investigate the existing phases, phase changes due to different content  to determine the absence of space particles in the production scaffold and to determine the size of blocks by x-ray diffraction (xrd). the mtt toxicity, apatite formation, as well as cell growth tests, were used to evaluate the biocompatibility and biodegradability of the porous scaffold. the scaffold degradation rate is determined after immersion in simulated body fluid (sbf) as well as phosphate buffer saline (pbs). the outcome shows that the sample with 10 wt% hla presents suitable mechanical and biological properties compared to the pure sample.