No abstract

The abnormal fibrillogenesis of amyloid peptides such as amyloid fibril and senior amyloid plaques, is associated with the pathogenesis of many amyloid diseases. Hence, modulation of amyloid assemblies is related to the possible pathogenesis of some diseases. Some two-dimensional nanomaterials, that is, graphene oxide, tungsten disulfide, exhibit strong modulation effects on the amyloid fibrillogenesis. Herein, the modulation effect of molybdenum disulfide on two amyloid peptide assemblies based on the label-free techniques is presented, including quartz crystal microbalance (QCM), AFM, and CD spectroscopy. MoS presents different modulating effects on the assembly of amyloid-β peptide (33-42) [Aβ (33-42)] and amylin (20-29), mainly owing to the distinct affinity between amyloid peptides and MoS . This is to our knowledge the first report of MoS as a modulator for amyloid aggregation. It enriches the variety of 2D nanomodulators of amyloid fibrillogenesis and explains the mechanism for the self-assembly of amyloid peptides, and expands the applications of MoS in biology.

The effects of Ga ion on the single layer graphene (SLG) have been studied by Raman spectroscopy (RS), SEM, and field-effect characterization. Under vacuum conditions, Ga ion-irradiation can induce disorders and cause red shift of 2D band of RS, rather than lattice damage in high quality SLG. The compressive strain induced by Ga ion decreases the crystalline size in SLG, which is responsible for the variation of Raman scattering and electrical properties. Nonlinear out-put characteristic and resistance increased are also found in the I-V measurement. The results have important implications during CVD graphene characterization and related device fabrication.