Single Particle Cathodoluminescence Spectroscopy with Sub-20 nm, Electron-Stable Phosphors

Lanthanide-doped nanophosphors have emerged as promising optical labels for high-resolution, “multicolor” electron microscopy. Here, we develop a library of 11 unique lanthanide-doped with average edge lengths 15.2 ± 2.0 nm (N = 4284). These consist an electron-stable BaYF5 host lattice doped at 25% atomic concentration the lanthanides Pr3+, Nd3+, Sm3+, Eu3+, Tb3+, Dy3+, Ce3+, Ho3+, Er3+, Tm3+, and Yb3+. Under ?100 pA/nm2 beam current in transmission microscope, each nanophosphor species exhibits strong cathodoluminescence spectra sharp characteristic emission lines lanthanide. The bright stability these nanoparticles enable not only ensemble, but also single-particle spectroscopy, which demonstrate BaYF5:Ln3+, where Ln3+ or Pr3+. Single-particle corresponds directly HAADF intensity across nanoparticles, confirming high spatial localization measured signal nanophosphors. Our synthesis characterization sub-20 nm, provides robust material platform to achieve single-molecule labeled correlative microscopy, critical foundation high-resolution correlation single molecules within context cellular ultrastructure.