Click chemistry has become one of the most powerful construction tools in the field of organic chemistry, materials science, and polymer science, as it offers hassle-free platforms for the high-yielding synthesis of novel materials and easy functionalization strategies. The absence of harsh reaction conditions or complicated workup procedures allowed the rapid development of novel biofunctional polymeric materials, such as biopolymers, tailor-made polymer surfaces, stimulus-responsive polymers, etc. In this review, we discuss various types of click reactions─including azide–alkyne cycloadditions, nucleophilic and radical thiol click reactions, a range of cycloadditions (Diels–Alder, tetrazole, nitrile oxide, etc.), sulfur fluoride exchange (SuFEx) click reaction, and oxime-hydrazone click reactions─and their use for the formation and study of biofunctional polymers. Following that, we discuss state-of-the-art biological applications of “click”-biofunctionalized polymers, including both passive applications (e.g., biosensing and bioimaging) and “active” ones that aim to direct changes in biosystems, e.g., for drug delivery, antiviral action, and tissue engineering. In conclusion, we have outlined future directions and existing challenges of click-based polymers for medicinal chemistry and clinical applications.

中文翻译：

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Click 生物功能聚合物的化学：从观察到引导细胞行为


点击化学已成为有机化学、材料科学和高分子科学领域最强大的构建工具之一，因为它为新型材料的高产率合成和简单的功能化策略提供了无忧的平台。由于没有苛刻的反应条件或复杂的后处理程序，可以快速开发新型生物功能聚合物材料，例如生物聚合物、定制的聚合物表面、刺激响应聚合物等。在这篇综述中，我们讨论了各种类型的点击反应，包括叠氮化物-炔烃环加成反应、亲核和自由基硫醇点击反应、一系列环加成反应（Diels-Alder、四唑、腈氧化物等）、硫氟交换 （SuFEx） 点击反应和肟-腙点击反应——以及它们在生物功能聚合物的形成和研究中的应用。之后，我们讨论了“点击”生物功能化聚合物的最新生物学应用，包括被动应用（例如，生物传感和生物成像）和旨在指导生物系统变化的“主动”应用，例如，用于药物递送、抗病毒作用和组织工程。总之，我们概述了基于点击的聚合物在药物化学和临床应用中的未来方向和现有挑战。