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A Ru-containing single chain nanoparticle (SCNP) was prepared in three steps using radical polymerization of pentafluorophenylacrylate, post-polymerization functionalization with three different alkylamines, and coordination of Ru. The polymer was characterized by 1 H NMR, 19 F NMR, UV-vis, and DLS. The catalytic activity of the Ru-SCNP for Ru-catalyzed cleavage of allylcarbamates was evaluated by fluorescence spectroscopy and a higher percent conversion and initial rate of reaction was observed when compared to that of the free catalyst in buffer and cell media. The catalytic SCNP was also shown to perform tandem catalysis with β-galactosidase. 

We report a modular approach in which a noncovalently cross-linked single chain nanoparticle (SCNP) selectively binds catalyst “cofactors” and substrates to increase both the catalytic activity of a Cu-catalyzed alkyne-azide cycloaddition reaction and the Ru-catalyzed cleavage of allylcarbamate groups compared to the free catalysts. 

Fluorescent linear dendronized polyols (LDPs) were prepared in two steps involving a ring-opening metathesis polymerization (ROMP) followed by acid-catalyzed deprotection. The resulting water-soluble fluorophores are compact in size (<6 nm) and show similar photostability compared to previously reported crosslinked dendronized polyols (CDPs) and significantly improved photostability compared to the free fluorophores. In contrast to the synthesis of CDPs, the production of LDPs requires less preparation time, synthetic effort, and significantly less Grubbs catalyst. The photophysical properties, including the photostability and emission wavelength of LDPs, can be further fine-tuned by incorporating different combinations of dendronized monomers and fluorophores. Interestingly, fluorescence resonance energy transfer (FRET) was observed when two different kinds of fluorophores were incorporated into the LDPs. This provides a new type of fluorophore with a large Stokes shift allowing fluorescence detection with reduced background overlap. Cytotoxicity and fluorescence imaging studies confirmed the biocompatibility of these LDPs, which make them potential candidates for biological applications.