In this article, we show that the redox properties of the regulatory peptide L-glutathione are affected by the presence of nickel oxide impurities within single-walled carbon nanotubes (SWCNTs). Glutathione is a powerful antioxidant that protects cells from oxidative stress by removing free radicals and peroxides. We show that the L-cysteine moiety in L-glutathione is responsible for the susceptibility to oxidation by metallic impurities present in the carbon nanotubes. These results have great significance for assessing the toxicity of carbon-nanotube materials. The SWCNTs were characterized by Raman spectroscopy, high-resolution X-ray photoelectron spectroscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy.

Here, we demonstrate that platelet graphite nanofibers (PGNFs) exhibit fast heterogeneous electron-transfer rates for a wide variety of compounds such as FeCl₃, ferrocyanide, dopamine, uric acid, ascorbic acid, and the reduced form of β-nicotinamide adenine dinucleotide. The electrochemical properties of PGNFs are superior to those of multiwalled carbon nanotubes (MWCNTs) or graphite microparticles (GMPs). Transmission electron microscopy and Raman spectroscopy reveal that this arises from the unique graphene sheet orientation of such platelet nanofibers, which accounts for their unparalleled high ratio of graphene edge planes versus basal planes.

Destičková grafitová nanovlákna (PGNFs) umožňují rychlý přenos elektronů při oxidaci či redukci mnoha sloučenin, například FeCl₃, ferrocyanid, dopamin, kyselina askorbová, kyselina močová a NADH. Elektrochemické vlastnosti PGNFs jsou mnohem lepší než vlastnosti uhlíkových nanotrubiček či grafitového prášku. TEM a Ramanova spektroskopie ukázala že je to z důvodu vyjímečně vysokého poměru hran grafénu vůči bazální rovině grafénu v PGNFs.