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- Mukherjee, Sourav P., et al.
(författare)
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Graphene Oxide Elicits Membrane Lipid Changes and Neutrophil Extracellular Trap Formation
- 2018
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Ingår i: Chem. - : Elsevier BV. - 2451-9294 .- 2451-9308. ; 4:2, s. 334-358
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the biological interactions of graphene-based materials is important for the safe use of these materials. Previous studies have explored the interaction between graphene oxide (GO) and macrophages but not the impact of GO on neutrophils, key cells of the immune system. Here, we synthesized GO sheets with differing lateral dimensions and showed by using an array of analytical and imaging techniques, including transmission and scanning electron microscopy, confocal microscopy, and time-of-flight secondary ion mass spectroscopy (ToF-SIMS), that GO elicited the formation of neutrophil extracellular traps (NETs). ToF-SIMS revealed pronounced perturbations of plasma membrane lipids, including a decrease in cholesterol and increased levels of oxidized cholesterol species. The induction of NETs was size dependent and associated with the production of mitochondrial reactive oxygen species and calcium influx. Importantly, antioxidant treatment reduced the production of NETs. These studies provide evidence that a previously undescribed biological effect of GO manifests through direct effects on membrane lipids. Graphene oxide (GO) is being investigated for various biomedical applications. Understanding the interactions between GO and living cells is of critical importance for the safe use of these materials in patients. In the present study, we identified effects of GO on neutrophils, the most common type of white blood cell. We first synthesized GO sheets of different sizes and carefully characterized the materials. Then, using various analytical and imaging techniques, we found that GO triggered so-called neutrophil extracellular traps or NETs. NETs are normally deployed by neutrophils to capture and destroy pathogens. We were able to show that GO caused significant changes in the lipid composition of the neutrophil cell membrane, whereby the oxidation of cholesterol set into motion a cascade of intracellular events leading to the formation of NETs. These studies show that GO acts directly on the neutrophil cell membrane and leads to the activation of a conserved anti-pathogen response. Graphene oxide (GO) is a promising material for a variety of biomedical and other applications. The increasing use of GO necessitates careful assessment of potential health hazards. Using primary neutrophils as a model, Mukherjee et al. show that GO elicits neutrophil extracellular traps. Furthermore, by using ToF-SIMS, the authors noted pronounced perturbations of plasma membrane lipids in cells exposed to GO.
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| 2. |
- Zhang, Qi, et al.
(författare)
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Muscle-like Artificial Molecular Actuators for Nanoparticles
- 2018
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Ingår i: Chem. - : Cell Press. - 2451-9308 .- 2451-9294. ; 4:11, s. 2670-2684
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Tidskriftsartikel (refereegranskat)abstract
- Muscle tissue performs crucial contraction/extension motions that generate mechanical force and work by consuming chemical energy. Inspired by this naturally created biomolecular machine, artificial molecular muscles are designed and synthesized to undertake linear actuation functions. However, most of these muscle-like actuators are performed at large ensembles, while to realize the nanoscale actuation at the single-to few-molecule level remains challenging. Herein, we developed an artificial muscle-like molecular actuator that can reversibly control the proximity of the attached nano-objects, gold nanoparticles, within the single-molecule length level by its stimuli-responsive muscle-like linear contraction/extension motion. The molecular actuation motion is accompanied by an optical signal output resulting from the plasmonic resonance properties of gold nanoparticles. Meanwhile, the thermal noise of the muscle-like molecular actuator can be overcome by integrating the optical signal over a sufficiently long period.
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