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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. 

We report a photo-triggered, base generating, base propagating degradable polyurethane that is triggered by 365 nm UV light irradiation. A small area of this polyurethane material can be exposed to 365 nm UV light irradiation to generate basic species that can initiate a base propagated degradation process within the bulk material leading to global degradation without the need for continous UV irradiation. The polymer was synthesized by a polycondensation polymerization of a small amount of o -nitrobenzene diol 2 , a large amount of Fmoc-based diol 3 , and hexylmethylene diisocyanate. Integrating both photosensitive and base-sensitive carbamate moieties into the polymer 1 backbone provides the UV light-triggered base propagating degradable polyurethane material. Degradation studies of polymer 1 using 1 H NMR and gel permeation chromatography (GPC) suggest that initial UV irradiation triggers the degradation of the photosensitive o -nitrobenzene carbamate linkages, releasing a primary amino group that causes a cascade of amines to form by further degrading the remaining Fmoc carbamate groups. A bulk polyurethane film was prepared using Fmoc-based triol 4 as a monomer. UV-irradiation of a small localized area of the film initiates the propagation throughout, leading to efficient bulk degradation of the entire material. The amine degradation products could be utilized to make a one-pot epoxy adhesive, showing a potential upcycling application of this self-propagating degradable polyurethane system. 

Small molecule targeting of DNA and RNA sequences has come into focus as a therapeutic strategy for diseases such as myotonic dystrophy type 1 (DM1), a trinucleotide repeat disease characterized by RNA gain‐of‐function. Herein, we report a novel template‐selected, reversible assembly of therapeutic agentsin situvia aldehyde‐amine condensation. Rationally designed small molecule targeting agents functionalized with either an aldehyde or an amine were synthesized and screened against the target nucleic acid sequence. The assembly of fragments was confirmed by MALDI‐MS in the presence of DM1‐relevant nucleic acid sequences. The resulting hit combinations of aldehyde and amine inhibited the formation of r(CUG)^expin vitro in a cooperative manner at low micromolar levels and rescued mis‐splicing defects in DM1 model cells. This reversible template‐selected assembly is a promising approach to achieve cell permeable and multivalent targeting viain situsynthesis and could be applied to other nucleic acid targets.