Non-blinking and photostable upconverted luminescence from single lanthanide-doped nanocrystals

The development of probes for single-molecule imaging has dramatically facilitated the study of individual molecules in cells and other complex environments. Single-molecule probes ideally exhibit good brightness, uninterrupted emission, resistance to photobleaching, and minimal spectral overlap with cellular autofluorescence. However, most single-molecule probes are imperfect in several of these aspects, and none have been shown to possess all of these characteristics. In this talk, I will show that individual lanthanide-doped upconverting nanoparticles (UCNPs) emit non-blinking and photostable near-infrared to visible upconverted luminescence when excited by a 980-nm continuous wave laser, suggesting that UCNPs are ideally suited for single-molecule imaging experiments.