The implementation of photocatalysts for controlled/living radical polymerization upon visible light harvesting has emerged as a robust and powerful technique for the user-friendly synthesis of well-structured polymers with composition, spatiotemporal, and sequence control. Nevertheless, the incompatibility of present synthetic protocols with environmentally benign media, such as water, still poses a detrimental threat to their practical applications. In this article, the adoption of hPGM-ZnTPP hollow microspheres with pH sensitivity and excellent dispersibility in various reaction media, which are firmly immobilized yet accessible catalytic metalloporphyrin components as heterogeneous photocatalysts for the photoinduced electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization, was demonstrated. Modulation of solution pH affected the performance of the catalysts, with the faster polymerization rate being observed in basic conditions rather than in acidic conditions. Besides, this strategy allowed the polymerization of a myriad of functional monomers to afford high polymerization yields and narrow polydispersities in different solvents including dimethyl sulfoxide and water, under a wide range of catalyst concentrations and without prior deoxygenation. By virtue of the robustness of hollow microspheres, multiple isolation and regeneration of the catalyst was accomplished through facile centrifugation with sustainable catalytic activity and negligible catalyst leaching, which in return largely mitigated or even eliminated the contamination and/or decomposition on the final polymer products.

Single-atom catalysts (SACs) composing of low-cost, earth-abundant metals, with two-dimensional material supports have displayed great potential in a wide range of electrochemical reactions, including CO2 reduction reaction (CO2RR) to convert...

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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-[4,5dimethylthiazol-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.

Magnetic Janus nanocomposites enabled robust toggling of RAFT photopolymerization of myriad monomer formulations using a single nanocatalyst with three orthogonal external physical manipulations.

Logic-controlled RAFT photopolymerization has become a powerful and eco-friendly toolkit to create well-defined macromolecular buildups while exhibiting composition, sequence and spatiotemporal control.

Precise control over molecular variables of grafted polymer brushes is of crucial importance for obtaining polymer nanocomposites with desirable architectures and physicochemical properties, yet it remains a significant synthetic challenge.

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