Fig. 13
(Reprinted/adapted with the permission from Wen et al. [65]. Copyright 2020 American Chemical Society)
ExM using trivalent anchoring (TRITON). Molecular design (a) and example (b) of a TRITON trivalent linker with a fluorescent reporter (Pacific Blue), reactive tetrafluorophenyl (TFP) ester for amine conjugation, and acrylamide monomer for grafting to the expansion microscopy polymer. c–h Expansion of HeLaP4 phospholipid membranes through lipid conjugation to a fluorescent TRITON trivalent linker. c–e Pre-expansion image (c) with magnified views (d, e) of the boxed areas. Scale bars: 25 μm (c, d) and 5 μm (e). f–h Post-expansion image (e) with magnified views (g, h) of the boxed areas. Scale bars: 7.8 μm (25 μm) (f, g) and 3.03 μm (10 μm) (h). i–k Immunostaining of α-tubulin of HeLa cell via direct grafting of oligo-conjugated secondary antibody and fluorescent oligo-based readout post-expansion. i Two-color imaging with a nuclear DAPI staining (cyan) and immunostaining of α-tubulin, visualized with readout oligo (Cy5,magenta). j The same staining as i but with the DAPI-channel removed to show the high signal-to-noise ratio and low background staining in the nucleus. k Magnified view of the boxed area in j. Scale bars: 3.03 μm (10 μm) (i, j) and 1.52 μm (5 μm) (k).