16-Mer ferritin-like protein templated gold nanoclusters for bioimaging detection of methylmercury in the brain of living mice

Abstract

Methylmercury (MeHg+) as one of the most potent neurotoxins is mainly accumulated in brain, so in vivo imaging detection of MeHg+ in brain is of crucial importance. Herein, we reported a photoluminescent nanosensor for MeHg+ detection in brain by integrating the bioimaging of gold nanoclusters (Au NCs), the fluorescence of Au NCs quenched by MeHg+, and the brain targeting feature of our recently constructed 16-mer shell-like protein (7A). First, Au NCs with 7A as a biotemplate (7A-Au NCs) by a facile and green method in water are fabricated for the first time, the fluorescence of which (∼650 nm) can be quenched by MeHg+ in a dose-dependent manner in vitro. Second, the as-prepared 7A-Au NCs are not only suitable for bioimaging of BBB endothelial cells, but also are an effective probe for bioimaging MeHg+ detection in a brain-specific manner. These findings open a door for MeHg+ detection in the brain of living subjects.