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Atherosclerosis is a leading cause of death worldwide. Antioxidant therapy has been considered a promising treatment modality for atherosclerosis, since reactive oxygen species (ROS) play a major role in the pathogenesis of atherosclerosis. We developed ROS-scavenging antioxidant nanoparticles (NPs) that can serve as an effective therapy for atherosclerosis. The newly developed novel antioxidant ROS-eliminating NPs were synthesized via reversible addition–fragmentation chain-transfer (RAFT) polymerization and act as a superoxide dismutase (SOD) mimetic agent. SOD is an anti-ROS enzyme which is difficult to use for passive delivery due to its low half-life and stability. Copolymers were synthesized using different feed ratios of 2,2,6,6-tetramethyl-4-piperidyl methacrylate (PMA) and glycidyl methacrylate (GMA) monomers and an anti-ROS nitroxyl radical polymer was prepared via oxidation. The copolymer was further conjugated with a 6-aminofluorescein via a oxirane ring opening reaction for intracellular delivery in RAW 264.7 cells. The synthesized copolymers were blended to create NPs (∼150 nm size) in aqueous medium and highly stable up to three weeks. The NPs were shown to be taken up by macrophages and to be cytocompatible even at high dose levels (500 μg mL−1). Finally, the nitroxide NPs has been shown to inhibit foam cell formation in macrophages by decreasing internalization of oxidized low-density lipoproteins.

Cardiovascular disease remains the number one cause of mortality and morbidity worldwide and includes atherosclerosis, which presents as a deadly and chronic inflammatory disease. The initial patho...

A key initiating step in atherosclerosis is the accumulation and retention of apolipoprotein B complexing lipoproteins within the artery walls. In this work, we address this exact initiating mechanism of atherosclerosis, which results from the oxidation of low-density lipoproteins (oxLDL) using therapeutic nanogels. We present the development of biocompatible polyethylene glycol (PEG) cross-linked nanogels formed from a single simultaneous cross-linking and co-polymerization step in water without the requirement for an organic solvent, high temperature, or shear stress. The nanogel synthesis also incorporates in situ noncovalent electrostatically driven template polymerization around an innate anti- inflammatory and anti-oxidizing paraoxonase-1 (PON-1) enzyme payload-the release of which is triggered because of matrix metalloproteinase responsive elements instilled in the PEG cross-linker monomer. The results obtained demonstrate the potential of triggered release of the PON-1 enzyme and its efficacy against the production of ox-LDL, and therefore a reduction in macrophage foam cell and reactive oxygen species formation.

Fabrication of polymeric foam with controlled porosity, good mechanical properties and electrical conductivity is demanding. However, developing such a porous system has remained a major challenge till today. Herein, we synthesized 1-methyl imidazole chloride ionic liquid grafted graphene oxide (G[MIM]Cl) and utilized it as an effective agent for controlling the strength, distribution and dimension of the pores of polyurethane foam system (ILF). On the contrary, the polymeric foams fabricated with pristine expandable graphite (GF) and the neat polymer (PUF) demonstrated a distorted cell structure and an uneven distribution of the pores. Additionally, the mechanical properties of GF and PUF were found to be inferior compared to those of ILF. The effect of surface modification of filler on the dispersion in the polyurethane matrix was also studied and compared with the dispersion of the un-functionalized filler. The ILF exhibited higher electrical conductivity over the GF and the PUF. Compressive stress-strain behavior and dynamic mechanical properties indicated that ILF demonstrated significant mechanical robustness compared to GF and PUF. These findings can be readily extended to the development of complex three dimensional polymeric architecture where controlled porosity is required.

The aim of this work was to study the effect of the ionic liquids (ILs) with respect to their anion type and the length of alkyl chain as dispersing and coupling agent in carbon nanotube (CNT) filled styrene butadiene rubber (SBR)/natural rubber (NR) blends. We characterized the ILs by their surface tensions whereupon their different values explain the different compatibilities of ILs with the rubber components and the filler. The wetting concept was further developed in order to experimentally characterize the effect of the rubber-IL and CNT-IL compatibility on the selective wetting of CNTs in rubber blends. It was found that all the used ILs improved the dispersion of CNTs in rubber blends significantly. During the mixing process the IL layer pre-bound to the CNT surface was replaced mainly by the NR phase and, partly, by the SBR phase. Thus, ILs cannot be used as coupling agent in this rubber blend. For the ILs with surface tension similar to that of CNTs the filler was partly wetted by IL that imparts the mixture a high electrical conductivity directly after the mixing process. This high conductivity can be used for triggering the vulcanization of the blend by means of the Joule heating. The preferential localization of ILs in the rubber matrix - but not in rubber-filler interphase - considerably influences the cross-link behavior of the vulcanizates and thus their final mechanical properties significantly.

We have analysed the effect of beam wander, jitter and boresight on the deviation of centroid of laser beam. It is seen to be wandering over a restricted range, though off the center of detector.