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Photoactive enzymes have been proposed as promising catalysts in photocontrolled reversible addition–fragmentation chain transfer (RAFT) polymerization. However, only a few enzymes have the photoactive properties suitable for initiating RAFT polymerization. Herein, we synthesize nanozymes with uniform and well-defined nanostructures through coassembly of albumin and photosensitizer. The resulting nanozymes feature the absorption bands of the monomeric photosensitizer, facilitating efficient light capture and electron transfer, which lead to high conversion efficiencies in photocontrolled RAFT polymerization. Importantly, the nanozymes show good reusability in multiple rounds of polymerizations and precise controllability of activation and deactivation of the reactions. This work represents the first realization of photoactive nanozymes that can be used for photocontrolled RAFT polymerization and thus will conceivably promote the rational design and catalytic applications of functional nanozymes. [Display omitted] • Nanozymes were constructed by coassembly of albumin and photosensitizer. • The nanozymes show uniform and well-defined nanostructures. • The photosensitizer in the nanozymes is in a monomeric state. • The nanozymes show high conversion efficiencies in RAFT polymerization. • The nanozymes have good reusability and precise controllability in polymerization. [ABSTRACT FROM AUTHOR]

Artificial light-harvesting systems were constructed by supramolecular assemblies with different morphology formed by cucurbit[n]urils-based host-guest complexation. • An amphiphilic anthracene compound (AP) was designed and synthesized. • AP can self-assemble into nanoparticles in water. • AP can form supramolecular assemblies with CB7 and CB8. • Light-harvesting systems can be constructed by the as-prepared assemblies. In the present work, we have designed and synthesized an amphiphilic pyridinium-functionalized anthracene (AP) compound, which can self-assemble into nanoparticles in aqueous solution. Moreover, AP can form AP-CB7 and AP-CB8 complexes with cucurbit[7]uril (CB7) and cucurbit[8]uril (CB8) through host-guest interactions in aqueous solution, in which the pyridinium moiety or the pyridinium and anthracene moieties were encapsulated into the cavity of CB7 or CB8. AP-CB7 and AP-CB8 can further self-assemble into nanospheres and nanorods, respectively. More interestingly, three light-harvesting systems were constructed in aqueous solution by using the positively charged supramolecular assemblies of AP, AP-CB7, and AP-CB8 as an energy donor and a negatively charged fluorescent dye Eosin Y disodium salt (EY) as an energy acceptor, in which three different energy donors based on different supramolecular assemblies with various structures exhibited entirely distinguishing energy transfer performance. The energy transfer efficiency and antenna effect are 17.8% and 10.3 for AP, 19.2% and 17.6 for AP-CB7, 22.3% and 15.1 for AP-CB8 after addition of the energy acceptor EY at a donor/acceptor ratio of 100:1, respectively. [ABSTRACT FROM AUTHOR]