A new strategy for specific imaging of neural cells based on peptide-conjugated gold nanoclusters

Abstract

Despite the significant progress in molecular imaging technologies that has been made in recent years, the specific detection of neural cells still remains challenging. Here, we suggest the use of gold nanoclusters (AuNCs) modified with a brain-targeting peptide as a potential imaging candidate for detecting neural cells in vitro and in mice. AuNCs of less than 10 nm (dynamic light scattering analysis) were first prepared using the “green” synthetic approach, and then a targeting peptide, rabies virus glycoprotein derived peptide (RDP), was conjugated to the AuNCs for improving the efficiency and specificity of neural cell penetration. The conjugate’s mechanism of cellular attachment and entry into neural cells was suggested to be receptor-mediated endocytosis through clathrin-coated pits. Also, noninvasive imaging analysis and animal studies indicated that the RDP-modified nanoclusters could concentrate in the brain and locate in neural cells. This study suggests the feasibility of using targeting peptide-modified nanoclusters for noninvasive imaging brain cells in vivo.

Promotion of SH-SY5Y Cell Growth by Gold Nanoparticles Modified with 6-Mercaptopurine and a Neuron-Penetrating Peptide

“…It is commonly known that RDP is a long peptide consisting of 39 amino acids, which is derived from rabies virus glycoprotein that has the capability of transport foreign macromolecules into neuronal cells [ 15 , 16 ]. In our previous study, cell uptake efficiency of gold nanoclusters was significantly enhanced when the nanoclusters were conjugated with RDP [ 17 ]. The mechanism of RDP penetration into cells may be associated with neural cell membrane γ-aminobutyric acid (GABA) receptor- or nicotinic acetylcholine receptor-mediated endocytosis [ 18 , 19 ].…”