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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]

Abstract In this work, we have designed and synthesized a bolaamphiphile of salicylaldehyde azine (BSA), which can form [2]pseudorotaxane with γ-cyclodextrin (BSA@γ-CD) in aqueous solution and exhibit remarkable enhancement of the fluorescence emission. Both BSA and BSA@γ-CD assembly can spontaneously form spherical aggregates in aqueous solution with diameter at about 30 nm and 20 nm, respectively. By using BSA and BSA@γ-CD as energy donor and sulforhodamine 101 (SR101) as energy acceptor, we fabricated two artificial light-harvesting systems in aqueous solution. Significantly, an efficient energy transfer process was revealed to occur between the BSA or BSA@γ-CD assembly and the loaded SR101 to obtain high energy transfer efficiency and antenna effect. More importantly, energy transfer efficiency and antenna effect can be greatly improved in these two systems only just by addition of γ-CD. Graphical abstract Two artificial light-harvesting systems based on a bolaamphiphile of salicylaldehyde azine moiety with γ-cyclodextrin and sulforhodamine 101 were fabricated in aqueous solution. Image 1 Highlights • Two artificial light-harvesting systems in aqueous solution are fabricated. • Sulforhodamine 101 is used as energy acceptor. • An efficient energy transfer process is revealed between energy donor and acceptor. • Energy transfer efficiency can be improved by the formation of [2]pseudorotaxane. [ABSTRACT FROM AUTHOR]

The supramolecular hyperbranched polymers have been constructed through host–guest interaction between TTFB and CB[8], which can self-assembly into spherical structures and form charge transfer complexes with TCNQ. • Supramolecular polymers were constructed based on TTF derivative and CB[8]. • Supramolecular polymers self-assembled into spherical aggregates. • Supramolecular polymers can form charge transfer complexes with TCNQ. • The charge transfer complexes self-assembled into crosslinked nanoparticles. In the present work, a four naphthyl-armed tetrathiafulvalene derivative (TTFB) was designed and synthesized through one-step reaction. Based on the host–guest interaction between naphthyl and cucurbit[8]uril (CB[8]), supramolecular hyperbranched polymers (SHPs) can be constructed in water, depending on hydrogen nuclear magnetic resonance (1H NMR) spectra, UV–vis absorption spectroscopy and diffusion-ordered NMR spectroscopy (DOSY). The self-assembly properties of the SHPs were further investigated by zeta potential analyzer, dynamic laser light scattering (DLS) and transmission electron microscopy (TEM) measurements, which exhibited positively charged spherical structures with the diameter at ~120 nm. More interestingly, the SHPs can interact with TCNQ (7,7,8,8-tetracyanoquinodimethane) to form charge transfer complexes through charge transfer interaction. Meanwhile, the self-assembly structures can be transformed from spherical structures to crosslinked nanoparticles in the charge transfer complexes state. [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]