Gelation at a temperature below the freezing point of a solvent is known as cryogelation, which has attracted attention in regenerative medicine due to its improved mechanical and structural properties. This study focuses on using cryogelation as a versatile method for fabricating biomimetic scaffolds with improved mechanical strength and larger pore sizes with potential for bone tissue engineering applications. Scaffolds comprising carboxymethyl chitosan/gelatin/nano-hydroxyapatite were formed through cryogelation. The effects of three parameters – namely, cross-linker concentration, mineral content and gelatin-to-polymer ratio – on physical, chemical and mechanical properties were investigated. In this work, MG63 cells were used for an in vitro assay. In addition, an in vivo assay was conducted to investigate the biocompatibility of the nanocomposite scaffolds. The results showed that all scaffolds have a porous structure with interconnected pores with a morphology similar to bone structure. Their pore size, porosity and swelling ratio decreased with an increased cross-linker concentration, while nano-hydroxyapatite had the opposite effect. X-ray diffraction results also showed that the inorganic phase retained its crystallinity in the substrate with a slight decrease in crystal size. In addition, the scaffolds showed no toxicity in either in vitro or in vivo studies. The obtained results showed that biomimetic cryogels based on carboxymethyl chitosan/gelatin/hydroxyapatite have potential for bone tissue engineering.

中文翻译：

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用于骨再生的羧甲基壳聚糖/明胶/羟基磷灰石仿生冷冻凝胶

在低于溶剂冰点的温度下进行凝胶化被称为冷冻凝胶化，由于其改进的机械和结构性能，它在再生医学中引起了人们的关注。本研究的重点是使用冷冻凝胶作为一种通用方法来制造具有更高机械强度和更大孔径的仿生支架，具有骨组织工程应用的潜力。通过冷冻凝胶化形成包含羧甲基壳聚糖/明胶/纳米羟基磷灰石的支架。研究了三个参数——即交联剂浓度、矿物质含量和明胶与聚合物的比例——对物理、化学和机械性能的影响。在这项工作中，MG63 细胞用于体外测定。此外，进行了体内测定以研究纳米复合材料支架的生物相容性。结果表明，所有支架均具有多孔结构，孔隙相互连通，形态类似于骨结构。它们的孔径、孔隙率和溶胀率随着交联剂浓度的增加而降低，而纳米羟基磷灰石则具有相反的效果。X 射线衍射结果还表明，无机相在基板中保持其结晶度，晶体尺寸略有减小。此外，支架在体外或体内研究中均未显示出毒性。获得的结果表明，基于羧甲基壳聚糖/明胶/羟基磷灰石的仿生冷冻凝胶具有用于骨组织工程的潜力。结果表明，所有支架均具有多孔结构，孔隙相互连通，形态类似于骨结构。它们的孔径、孔隙率和溶胀率随着交联剂浓度的增加而降低，而纳米羟基磷灰石则具有相反的效果。X 射线衍射结果还表明，无机相在基板中保持其结晶度，晶体尺寸略有减小。此外，支架在体外或体内研究中均未显示出毒性。获得的结果表明，基于羧甲基壳聚糖/明胶/羟基磷灰石的仿生冷冻凝胶具有用于骨组织工程的潜力。结果表明，所有支架均具有多孔结构，孔隙相互连通，形态类似于骨结构。它们的孔径、孔隙率和溶胀率随着交联剂浓度的增加而降低，而纳米羟基磷灰石则具有相反的效果。X 射线衍射结果还表明，无机相在基板中保持其结晶度，晶体尺寸略有减小。此外，支架在体外或体内研究中均未显示出毒性。获得的结果表明，基于羧甲基壳聚糖/明胶/羟基磷灰石的仿生冷冻凝胶具有用于骨组织工程的潜力。而纳米羟基磷灰石则有相反的效果。X 射线衍射结果还表明，无机相在基板中保持其结晶度，晶体尺寸略有减小。此外，支架在体外或体内研究中均未显示出毒性。获得的结果表明，基于羧甲基壳聚糖/明胶/羟基磷灰石的仿生冷冻凝胶具有用于骨组织工程的潜力。而纳米羟基磷灰石则有相反的效果。X 射线衍射结果还表明，无机相在基板中保持其结晶度，晶体尺寸略有减小。此外，支架在体外或体内研究中均未显示出毒性。获得的结果表明，基于羧甲基壳聚糖/明胶/羟基磷灰石的仿生冷冻凝胶具有用于骨组织工程的潜力。