Fig. 4
Immunofluorescence labeling of cellular cytoskeleton protein desmin with antibody-conjugated UCNPs and super-resolution imaging. a The multiphoton imaging under 975-nm excitation of some cytoskeleton structures and desmin proteins in HeLa cancer cells incubated with anti-desmin primary antibody and immunostained with UCNPs (11.8 ± 2.2 nm in diameter) bioconjugated with goat anti-rabbit IgG secondary antibody. b The same region with a imaged in the super-resolution mode (975-nm excitation and the 810-nm STED laser beam). Scale bars: 2 μm. c–n Magnified areas selected from a and b (marked by white dotted squares) and line profile analyses; images in c, f, i, and l are taken from the white dotted squares in a; Images in d, g, j, and m are taken from the white dotted squares in b. e, h, k, n Line profiles analyses of several areas indicated by arrow heads in c and d, f and g, i and j, and l and m, respectively
