Nonblinking Plasmonic Quantum Dot Assemblies for Multiplex Biological Detection

Fayi Song, Peter S Tang, Holly Durst, David T Cramb, Warren CW Chan

Angewandte Chemie, Volume 124, Issue 35 | DOI: 10.1002/ange.201201872


Optical labels enable visualization and detection of molecules, cells, and tissues. These labels have limited multiplexing capabilities, blink on/off at the single-molecule level, and, in many cases, they have low brightness. We address each of these issues through the development of a sub-50nm barcoded optical label system by coating fluorescent quantum dots onto the surface of plasmonic nanoparticles using a layerby-layer polyelectrolyte deposition strategy. We denote these gold nanoparticle–quantum dot hybrid structures as GQHs. This probe design strategy has the potential to create thousands of uniquely emitting nonblinking fluorescent probes. These barcodes can be further conjugated to biorecognition molecules, target cells, and have prolonged intracellular retention with minimal toxicity. Our results demonstrate that plasmonic nanoparticles are ideal templates for designing nanoscale barcodes …