This Review gives a brief introduction to hydrogels formed through click chemistry for applications in tissue engineering. Specifically, we focus on three representative click chemistry mechanisms: Diels–Alder reactions, azide–alkyne cycloaddition, and thiol–ene chemistry. Apart from that, we also discuss photoinitiated chain growth polymerization, which also has fast kinetics. The chemical mechanisms of these reactions, along with their advantages and disadvantages, are presented. These gelation methods are compared and contrasted with other methods of forming hydrogels. Further, we offer an insight on the fabrication of click chemistry hydrogels from a material selection perspective. Commonly used materials from both synthetic and naturally derived polymer families were selected and discussed with their special features and drawbacks in fabricating hydrogels used in tissue engineering applications. At the end, the impact of cross-linking mechanisms and hydrogels properties on the host response is discussed. In conclusion, click reactions are modular and stereospecific. These reactions proceed rapidly with high selectivity, which means they have the potential to be formed in situ with minimal interference on biological processes. In order to achieve optimal hydrogels for tissue engineering applications, it is important to consider different design principles and material fabrication strategies to develop optimal hydrogels for regenerative medicine applications.

中文翻译：

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单击化学和材料选择，以在组织工程应用中原位制备水凝胶

这篇综述简要介绍了通过点击化学形成的水凝胶在组织工程中的应用。具体来说，我们关注于三种代表性的点击化学机理：狄尔斯-阿尔德反应，叠氮化物-炔烃环加成反应和硫醇-烯化学反应。除此之外，我们还讨论了光引发的链增长聚合，它也具有快速的动力学。介绍了这些反应的化学机理，以及它们的优缺点。将这些胶凝方法与其他形成水凝胶的方法进行了比较和对比。此外，我们从材料选择的角度对点击化学水凝胶的制备提供了见解。选择了来自合成和天然衍生聚合物家族的常用材料，并讨论了它们在制造用于组织工程应用中的水凝胶时的特殊功能和缺点。最后，讨论了交联机理和水凝胶性质对宿主反应的影响。总之，点击反应是模块化的和立体声特定的。这些反应以高选择性快速进行，这意味着它们有可能形成原位，对生物过程的干扰最小。为了获得用于组织工程应用的最佳水凝胶，重要的是考虑不同的设计原理和材料制造策略以开发用于再生医学应用的最佳水凝胶。