Key Laboratory of Biomedical Polymers of Ministry of Education, College of Chemistry and Molecular Science, Wuhan University, Wuhan, Hubei 430072, P. R. China.
Department of Chemical and Biological Engineering, Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology, William Mong Institute of Nano Science and Technology, and Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, P. R. China.
ACS Appl Mater Interfaces. 2021 Sep 22;13(37):44488-44496. doi: 10.1021/acsami.1c13770. Epub 2021 Sep 13.
Light-driven polymerization, such as photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization, enables biological benign conditions and versatile functional polymer structure design, which is readily used in protein-polymer bioconjugates. However, conventional metalloporphyrinic homogeneous catalysts for PET-RAFT polymerization suffer from limited aqueous solubility and tedious purification. Here we demonstrate the design of PET-RAFT photocatalyst from the reticular assembled Zr-porphyrinic metal-organic frameworks (MOFs), along with a biomacromolecule-based chain transfer agent, as efficient bioconjugation tools in water. Our methodology offers manufacturing advantages on bioconjugates under mild conditions such that MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) and cytotoxicity assays have shown the preservation of the protein integrity, bioactivity, and high cell viability after PET-RAFT polymerization. We find that the fast kinetics are benefiting from the ultrahigh loading of metalloporphyrins in MOF-525-Zn. This heterogeneous catalyst also allows us to maintain living characteristics to incorporate myriads of monomers into block copolymers. Other advantages like easy postreaction purification, reusability, and high oxygen tolerance even in an open system are demonstrated. This study provides a tool of highly efficient heterogeneous photocatalysts for polymer-protein bioconjugation in aqueous media and paves the road for biological applications.
光驱动聚合，如光诱导电子/能量转移-可逆加成-断裂链转移（PET-RAFT）聚合，可在生物条件下实现，并且能够设计多功能聚合物结构，因此在蛋白质-聚合物生物偶联物中得到了广泛应用。然而，用于 PET-RAFT 聚合的传统金属卟啉均相催化剂水溶性有限且纯化繁琐。在此，我们展示了基于网状组装的 Zr-卟啉金属有机骨架（MOFs）的 PET-RAFT 光催化剂的设计，以及基于生物大分子的链转移剂，作为在水中有效的生物偶联工具。我们的方法在温和条件下为生物偶联物提供了制造优势，MTT（3-[4,5-二甲基噻唑-2-基]-2,5-二苯基四氮唑溴盐）和细胞毒性测定表明，在 PET-RAFT 聚合后，蛋白质完整性、生物活性和高细胞活力得以保留。我们发现超快动力学受益于 MOF-525-Zn 中超高负载的金属卟啉。这种非均相催化剂还使我们能够保持聚合的活性质，将无数单体纳入嵌段共聚物中。还展示了其他优点，如易于后反应纯化、可重复使用性和高耐氧性，甚至在开放体系中也是如此。这项研究为水相聚合物-蛋白质生物偶联提供了高效的非均相光催化剂工具，并为生物应用铺平了道路。
