Ultrasmall,elementary and highly translational nanoparticle X-ray contrast media from amphiphilic iodinated statistical copolymers

To expand the single-dose duration over which noninvasive clinical and preclinical cancer imaging can be conducted with high sensitivity,and well-defined spatial and temporal resolutions,a facile strategy to prepare ultrasmall nanoparticulate X-ray contrast media(nano-XRCM)as dual-modality imaging agents for positron emission tomography(PET)and computed tomography(CT)has been established.Synthesized from controlled copolymerization of triiodobenzoyl ethyl acrylate and oligo(ethylene oxide)acrylate monomers,the amphiphilic statistical iodocopolymers(ICPs)could directly dissolve in water to afford thermodynamically stable solutions with high aqueous iodine concentrations(>140 mg iodine/mL water)and comparable viscosities to conventional small molecule XRCM.The formation of ultrasmall iodinated nanoparticles with hydrodynamic diameters of ca.10 nm in water was confirmed by dynamic and static light scattering techniques.In a breast cancer mouse model,in vivo biodistribution studies revealed that the64Cu-chelator-functionalized iodinated nano-XRCM exhibited extended blood residency and higher tumor accumulation compared to typical small molecule imaging agents.PET/CT imaging of tumor over 3 days showed good correlation between PET and CT signals,while CT imaging allowed continuous observation of tumor retention even after 10 days post-injection,enabling longitudinal monitoring of tumor retention for imaging or potentially therapeutic effect after a single administration of nano-XRCM.

Microencapsulated paraffin as a tribological additive for advanced polymeric coatings

Numerous tribological applications,wherein the use of liquid lubricants is infeasible,require adequate dry lubrication.Despite the use of polymers as an effective solution for dry sliding tribological applications,their poor wear resistance prevents the utilization in harsh industrial environment.Different methods are typically implemented to tackle the poor wear performance of polymers,however sacrificing some of their mechanical/tribological properties.Herein,we discussed the introduction of a novel additive,namely microencapsulated phase change material(MPCM)into an advanced polymeric coating.Specifically,paraffin was encapsulated into melamine-based resin,and the capsules were dispersed in an aromatic thermosetting co-polyester(ATSP)coating.We found that the MPCM-filled composite exhibited a unique tribological behavior,manifested as“zero wear”,and a super-low coefficient of friction(COF)of 0.05.The developed composite outperformed the state-of-the-art polytetrafluoroethylene(PTFE)-filled coatings,under the experimental conditions examined herein.