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Updated: Feb 8, 2026

Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
Three-Dimensional Tracking of Quantum Dot-Conjugated Molecules in Living Cells
Lucia Gardini1,2, Martino Calamai1,2, Hiroyasu Hatakeyama3
1LENS-European Laboratory for Non-linear Spectroscopy, Sesto Fiorentino, Italy.
Abstract:
Here, we describe protocols for three-dimensional tracking of single quantum dot-conjugated molecules with nanometer accuracy in living cells using conventional fluorescence microscopy. The technique exploits out-of-focus images of single emitters combined with an automated pattern-recognition open-source software that fits the images with proper model functions to extract the emitter coordinates. We describe protocols for targeting quantum dots to both membrane components and cytosolic proteins.
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