Biomolecular interactions of carbon nanotubes with amyloid-β proteins

Carbon nanotubes (CNTs) have attracted considerable attention due to their prominent advantages of adsorption, tensile strength, electronic conductivity, and surface functionalization using proteins or functional groups. Recent studies suggested that carbon quantum dots, graphene, and hybrid materials doped with CNTs can effectively inhibit the fibrillization of amyloid-β proteins (Aβ), which represents a significant signal of early Alzheimer's disease (AD). The investigations on the CNT-Aβ interaction can elucidate the reaction mechanism and reveal the basic reaction phenomena of CNTs in AD patients. This review systematically introduces the basic characteristics and biosafety of CNTs, the physicochemical properties of Aβ, and the CNT-Aβ interaction mechanism. We mainly summarize the mechanisms of different functional group modifications on the surface of CNTs for Aβ interactions, and even the interactions between different-diameter CNTs and Aβ. In addition, we also introduce the "protein crown" formed on the CNT surface, leading to the various CNT-Aβ interactions. Our work provides a theoretical basis for the biomedical application of CNTs and its applications in AD therapy/treatment.