Photoactive Bismuth Vanadate Structure for Light‐Triggered Dissociation of Alzheimer's β‐Amyloid Aggregates

Abstract

AbstractBismuth vanadate (BiVO4) is an attractive, low‐cost n‐type semiconductor that exhibits excellent photoelectrocatalytic properties, chemical stability, and biocompatibility. This study reports a newly discovered function of BiVO4 dissociating highly stable, self‐assembled amyloid aggregates associated with Alzheimer's disease. A visible light‐active, nanoporous BiVO4 platform is developed to break β‐amyloid (Aβ) assemblies and alleviate Aβ aggregate‐induced toxicity. Multiple photochemical and microscopic analyses reveal that β‐sheet‐rich, long Aβ fibrils are effectively destabilized and broken into small‐sized, soluble species by BiVO4 photoelectrode under illumination of a white light‐emitting diode and an anodic bias. The photoactivated BiVO4 under anodic bias generates oxidative stress, such as superoxide ions and hole‐derived hydrogen peroxide, which causes photooxidation of Aβ residues and irreversible disassembly of Aβ aggregates. The efficacy of photoelectrocatalytic dissociation of Aβ aggregates is enhanced by Mo‐doped BiVO4, which facilitates the separation of electron–hole pairs by improving electron‐transport properties of BiVO4. Furthermore, it is verified that both pristine and Mo‐doped BiVO4 photoelectrodes are nontoxic and effective in reducing Aβ‐associated cytotoxicity. The work shows the potential of BiVO4‐based photoelectrode platforms for the dissociation of neurotoxic, highly stable Aβ assemblies using light energy.