Abstract：
Bone tissue engineering offers a promising alternative to stimulate the regeneration of damaged tissue, overcoming the limitations of conventional autografts and allografts. Recently, titanium alloy (Ti) implants have garnered significant attention for treating critical-sized bone defects, especially with the advancement of 3D printing technology. Although Ti alloys have impressive versatility, their lack of cellular adhesion, osteogenic and antibacterial properties are significant factors that contribute to their failure. Hence, to overcome these obstacles, this study aimed to incorporate osteoinductive and antibacterial cue-loaded hydrogels into 3D-printed Ti (3D-Ti) scaffolds. 3D-Ti scaffolds were synthesized using the direct metal laser sintering method and loaded with a gelatin (Gel) hydrogel containing strontium-doped silver nanoparticles (Sr-Ag NPs). Compared with Ag NPs, Sr-doped Ag NPs increased the expression of Runx2 mRNA, which is a key bone transcription factor. We subjected the bioactive 3D-hybrid scaffolds (3D-Ti/Gel/Sr-Ag NPs) to physicochemical and material characterization, followed by cytocompatibility and osteogenic evaluation. The microporous and macroporous topographies of the scaffolds with Sr-Ag NPs showed increased Runx2 expression and matrix mineralization, with potent antibacterial properties. Therefore, the 3D-Ti scaffolds incorporated with Sr-Ag NP-loaded Gel hydrogels favored osteoblast differentiation and antibacterial activity, indicating their potential for orthopedic applications.
摘要：
骨组织工程提供了一种有希望的替代方法来刺激受损组织的再生，克服了传统自体移植和同种异体移植的局限性。最近,钛合金（Ti）植入物在治疗临界尺寸的骨缺损方面引起了极大的关注，尤其是随着3D打印技术的进步。尽管钛合金具有令人印象深刻的多功能性，它们缺乏细胞粘附，成骨和抗菌性能是导致其失败的重要因素。因此，为了克服这些障碍，这项研究旨在将骨诱导和抗菌提示加载的水凝胶纳入3D打印的Ti（3D-Ti）支架中。使用直接金属激光烧结方法合成3D-Ti支架，并加载含有锶掺杂银纳米颗粒（Sr-AgNP）的明胶（凝胶）水凝胶。与AgNPs相比，Sr掺杂的AgNPs增加了Runx2mRNA的表达，这是一个关键的骨转录因子。我们对生物活性3D混合支架（3D-Ti/Gel/Sr-AgNPs）进行物理化学和材料表征，其次是细胞相容性和成骨评价。Sr-AgNP支架的微孔和大孔形貌显示Runx2表达和基质矿化增加，具有强大的抗菌性能。因此,掺入Sr-AgNP-Gel水凝胶的3D-Ti支架有利于成骨细胞分化和抗菌活性，表明它们在骨科应用中的潜力。
