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Monovalent, reduced-size quantum dots for imaging receptors on living cells.

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 monovalency prevented EphA3 tyrosine kinase activation.

SUBMITTER: Howarth M

PROVIDER: S-EPMC2637151 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Monovalent, reduced-size quantum dots for imaging receptors on living cells.

Howarth Mark M Liu Wenhao W Puthenveetil Sujiet S Zheng Yi Y Marshall Lisa F LF Schmidt Michael M MM Wittrup K Dane KD Bawendi Moungi G MG Ting Alice Y AY

Nature methods 20080420 5

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]

PMID: 18425138

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