Modification of natural and composite alginate hydrogels and repair of bone defect with composite systems
Fan Yi, Liu Yadong, Cui Yutao, Liu He, Tian Yuhang, Li Shaorong, Wang Gan, Wu Dankai, Peng Chuangang
Department of Orthopedics, Second Hospital of Jilin University, Changchun 130041, Jilin Province, China
Abstract: BACKGROUND: As a cell scaffold material for bone tissue engineering, alginate hydrogel has attracted attention due to its good biocompatibility and renewable characteristics. However, due to the slow degradation and instability of natural alginate hydrogel, it may not achieve the desired effect in the body environment. Therefore, modification of natural alginate hydrogel and construction of its composite system are needed to meet the needs of bone repair.
OBJECTIVE: To introduce the structure and modification strategy of natural alginate hydrogel, and the construction strategy of composite alginate hydrogel. It emphasizes the various functions of alginate hydrogel and its composite system in different bone defect repair, and summarizes the current research focus and prospects the future development trend.
METHODS: With “alginate hydrogel, bone defect, bone repair, alginate, bone defect, bone repair” as the key words, the author searched related articles on PubMed, Web of Science, Medline, Wanfang, CNKI and VIP databases from 1995 to 2021. Totally 69 articles were analyzed after screening.
RESULTS AND CONCLUSION: (1) Through oxidation, γ-ray irradiation and other treatments, alginate hydrogel can achieve faster biodegradability, and different crosslinking methods can make it have different chemical structures. (2) Through the construction of the composite system, the alginate hydrogel and the composite system can be used as carriers for cells, bioactive factors and drugs, and can be used alone or in combination with other stents. (3) Due to the above complex properties, alginate gel and its composite system have a good prospect in the repair of bone defects, and in some existing research reports, complete bone bridging of critical bone defects has been achieved. Alginate hydrogel composite systems provide potential solutions for bone repair. Accelerated healing of bone defects and critical bone defect healing are achieved through controlled delivery of local bioactive substances. (4) In the repair of large segment and load-bearing bone defects, other scaffolds with high mechanical strength can be combined to enhance the bone integration capability of other scaffolds while providing mechanical load-bearing. These solutions can adapt to different requirements for bone defect repair. (5) To sum up, alginate gel and its composite system have shown a good effect on promoting bone tissue repair in animal experiments, providing a potential way for bone tissue engineering to repair bone defects. However, there is no systematic clinical trial at present, so more research and exploration are needed before it actually serves clinical work.
Key words: alginate hydrogel, alginate, hydrogel, bone defect, bone repair, bone tissue engineering, biomaterial, review