The objective of this study is to develop biomimetic chitosan: gelatin (CH:Gel) cryogels for bone tissue engineering, combining the biological recognition of natural polymers with the distinguished interconnected porosity of cryogels, and biomimicking properties of bone like hydroxyapatite. The control of the biomineralization process onto biomaterials should be evaluated before clinical application. Therefore, the effect of chitosan and gelatin ratios on the final properties of the cryogels were investigated. FTIR, XRD, and SEM analysis indicated that the SBF coating exhibited similar characteristics to hydroxyapatite. The cryogels showed good biocompatibility with L929 mouse fibroblasts. Clinical outcomes and gross pathological examination showed that neither necrosis nor foreign body reaction was noted at the end of implantation. The biomimetically mineralized scaffold was found to be non‐irritant and non‐toxic for bone tissue. The biological performance and favorable properties demonstrated that the SBF coated CH:Gel cryogel can be a promising biomimetic scaffold for bone tissue engineering applications.

Polymeric scaffolds produced by cryogelation technique have attracted increasing attention for tissue engineering applications. Cryogelation is a technique which enables to produce interconnected porous matrices from the frozen reaction mixtures of polymers or monomeric precursors. Chitosan is a biocompatible, biodegradable, nontoxic, antibacterial, antioxidant, and antifungal natural polymer that is obtained by deacetylation of chitin, which is mostly found in the exoskeleton of many crustaceans. In this study, chitin was chemically isolated from the exoskeleton of blue crab (Callinectes sapidus). Callinectes sapidus samples were collected from a market, as a waste material after it has been consumed as food. Demineralization, deproteinization, and decolorization steps were applied to the samples to obtain chitin. Chitosan was prepared from isolated chitin by deacetylation at high temperatures. The chemical composition of crab shell, extracted chitin and chitosan were characterized with FTIR analysis. Moreover, in order to determine the physicochemical and functional properties of the produced chitosan, solubility, water uptake, and oil uptake analysis were performed. Chitosan cryogel scaffolds were prepared by crosslinking reaction at cryogenic conditions at constant amount of chitosan (1%, w/v) with different ratios of glutaraldehyde (1, 3, and 6%, v/v) as crosslinker. The chemical structure of the scaffolds were examined by FTIR. Also, the water uptake capacity of scaffolds have been determined. Collectively, the results suggested that the characterized chitosan cryogels can be potential scaffolds to be used in tissue engineering applications.