Monovalent, reduced-size quantum dots for imaging receptors on living cells.
Journal:
Nat. Methods 2008 MayAuthors:
Howarth M, Liu W, Puthenveetil S, Zheng Y, Marshall LF, Schmidt MM, Wittrup KD, Bawendi MG, Ting AY
Abstract
We describe a method to generate monovalent quantum dots (QDs) using agarose gel electrophoresis. We passivated QDs with a carboxy-terminated polyethylene-glycol ligand, yielding particles with half the diameter of commercial QDs, which we conjugated to a single copy of a high-affinity targeting moiety (monovalent streptavidin or antibody to carcinoembryonic antigen) to label cell-surface proteins. The small size improved access of QD-labeled glutamate receptors to neuronal synapses, and monoval
...[more]ency prevented EphA3 tyrosine kinase activation.[less]
Mesh Headings:
Animals, Carcinoembryonic Antigen, Cell Survival, Cells, Cells, Cultured, Electrophoresis, Agar Gel, Fluorescent Dyes, Image Processing, Computer-Assisted, Ligands, Nanotechnology, Polyethylene Glycols, Quantum Dots, Rats, Receptors, Cell Surface, Receptors, Glutamate, Staining and Labeling, Streptavidin, Synapses