STED nanoscopy with fluorescent quantum dots

作者：Janina Hanne, Henning J. Falk, Frederik Görlitz, Patrick M. Hoyer, Johann Engelhardt, Steffen J. Sahl, Stefan W. Hell · 发表于：Nature Communications · 年份：2015 · DOI：10.1038/ncomms8127 · 被引用次数：218 · 研究领域：Quantum Dots Synthesis And Properties、Near-Field Optical Microscopy、Advanced Fluorescence Microscopy Techniques

The widely popular class of quantum-dot molecular labels could so far not be utilized as standard fluorescent probes in STED (stimulated emission depletion) nanoscopy. This is because broad quantum-dot excitation spectra extend deeply into the spectral bands used for STED, thus compromising the transient fluorescence silencing required for attaining super-resolution. Here we report the discovery that STED nanoscopy of several red-emitting commercially available quantum dots is in fact successfully realized by the increasingly popular 775 nm STED laser light. A resolution of presently ∼ 50 nm is demonstrated for single quantum dots, and sub-diffraction resolution is further shown for imaging of quantum-dot-labelled vimentin filaments in fibroblasts. The high quantum-dot photostability enables repeated STED recordings with >1,000 frames. In addition, we have evidence that the tendency of quantum-dot labels to blink is largely suppressed by combined action of excitation and STED beams. Quantum-dot STED significantly expands the realm of application of STED nanoscopy, and, given the high stability of these probes, holds promise for extended time-lapse imaging.