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Fluorine-containing polymeric materials are receiving increasing attention as imaging probes in fluorine-19 magnetic resonance imaging (F MRI), for example to enable quantitative in vivo detection of cells. Here we describe the one-pot polymerization synthesis of F-containing functional poly(oligo(ethylene glycol) methyl ether methacrylate-co-2,2,2-trifluoroethyl acrylate-b-poly(styrene-co-3-vinylbenzaldehyde) (poly(OEGA-co-TFEA)-b-poly(St-co-VBA)) copolymers as a new class of fluorinated MRI agent. A range of nanoparticle morphologies, including spheres, worm-like particles, and vesicles were formed as a consequence of polymerization-induced self-assembly (PISA). It was found that the extent of cell uptake strongly depends on the morphology of the nano-objects, with preferable uptake for worm-like particles compared to spherical nanoparticles and vesicles. All the nano-objects have a single resonance in theF NMR spectrum with relatively short MRI relaxation times, which were independent of the morphology of the nano-objects. These results confirm that these polymeric nano-objects of varied morphologies are promising as F MRI imaging agents for use in tracking of cells and selective MRI.

A novel method for synthesis of polymeric nano-objects via polymerization-induced self-assembly in a CO2-expanded medium has been developed.

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Developing inexpensive and highly efficient CO2 air capture technologies is an important solution for solving the greenhouse problem. In this work, we used the low-cost quaternized chitosan (QCS)/poly­(vinyl alcohol) (PVA) hybrid aerogels with quaternary ammonium groups and hydroxide ions to reversibly capture CO2 from ambient air by humidity swing. The CO2 capture capacity and adsorption rate of the aerogels were investigated over the temperature range 10–30 °C. The CO2 capture capacity of the aerogels was measured to be about 0.18 mmol/g, which is 38% higher than the state-of-the-art commercial membrane. In addition, we proposed a modified pseudo-first-order kinetic model considering both the CO2 adsorption and the H2O desorption, which describes the experimental results very well. For the first time, the moisture-swing CO2 adsorbent is built by low-cost biomass material, which opens up a new approach for the design of the moisture-swing CO2 adsorbent.