Objective To introduce the development of dextran-based hydrogel and its drug delivery system in drug sustained and/or controlled release, and to investigate their application in tissue engineering.Methods Related literature was extensively reviewed and comprehensively analyzed. Results In recent years, great progress was made in the studies of dextran-based hydrogels and study on dextran-based intelligent materials became an investigative hotspot especially in tissue engineering. Conclusion Dextran based hydrogel is considered to be a good potential material in field of drug delivery and tissue engineering. Endowed with new characteristics, a series of intelligent biomaterials can be derived from dextran-based hydrogels, which can be widely used in biomedicine. Further study should be done on the industrialization of its interrelated production.
In cases where a tracheal injury exceeds half the length of the adult trachea or one-third of the length of the child trachea, it becomes difficult to perform end-to-end anastomosis after tracheal resection due to excessive tension at the anastomosis site. In such cases, tracheal replacement therapy is required. Advances in tissue engineering technology have led to the development of tissue engineering tracheal substitutes, which have promising applications. Hydrogels, which are highly hydrated and possess a good three-dimensional network structure, biocompatibility, low immunogenicity, biodegradability, and modifiability, have had wide applications in the field of tissue engineering. This article provides a review of the characteristics, advantages, disadvantages, and effects of various hydrogels commonly used in tissue engineering trachea in recent years. Additionally, the article discusses and offers prospects for the future application of hydrogels in the field of tissue engineering trachea.
Collagen contains abundant cell binding motifs, which are conducive to adhesion, migration, and differentiation, maintain cell vitality and promote cell proliferation. However, pure collagen hydrogel has some shortcomings such as poor mechanical properties, poor thermal stability and fast degradation. Numerous studies have shown that the properties of collagen can be improved by combining it with natural polysaccharides such as alginate, chitosan, hyaluronic acid and cellulose. In this paper, the research status and biological application fields of four kinds of composite hydrogels, including collagen-alginate composite hydrogels, collagen-chitosan hydrogels, collagen-hyaluronic acid hydrogels and collagen-cellulose hydrogels, were summarized. The common preparation methods of four kinds of composite hydrogels were introduced, and the future development direction of collagen-based composite hydrogels was prospected.
The research on vitreous substitutes aims to find materials that can replace the functions of natural vitreous and be used to treat vitreoretinal diseases. Traditional substitutes such as gases and silicone oil have many drawbacks. However, hydrogels are regarded as highly potential substitutes due to their high water content, good biocompatibility, adjustable physical and chemical properties, and potential for controlled drug release. Researchers have developed two types of in-situ cross-linked hydrogels: chemical cross-linking and physical cross-linking. Chemical cross-linked hydrogels achieve in-situ gelation by forming chemical covalent bonds, showing good stability and degradability, but still require precise control of the degradation rate and the safety of degradation products. Physical cross-linked hydrogels utilize physical or supramolecular interactions between polymer chains to achieve in-situ gelation, having low toxicity and self-repairing properties, but they degrade too quickly and require a combination of physical and chemical cross-linking to extend the material's retention time. Additionally, researchers have explored in-situ cross-linked hydrogels loaded with anti-inflammatory, antioxidant, or anti-proliferative drugs for vitreoretinal disease, elevating vitreous substitutes from simple physical filling to an active treatment level. Future research needs to further optimize the comprehensive performance of hydrogels and deeply study their long-term biological activity impact on the intraocular microenvironment to promote their clinical translation.