posted on 2024-03-05, 16:37authored byZe-Hua Wu, Xingfu Zhu, Qiqi Yang, Yulian Zagranyarski, Krishna Mishra, Hilmar Strickfaden, Ronald P. Wong, Thomas Basché, Kaloian Koynov, Mischa Bonn, Chen Li, Xiaomin Liu, Klaus Müllen
Organic near-infrared
(NIR) photoblinking fluorophores are highly
desirable for live-cell super-resolution imaging based on single-molecule
localization microscopy (SMLM). Herein we introduce a novel small
chromophore, PMIP, through the fusion of perylenecarboximide
with 2,2-dimetheylpyrimidine. PMIP exhibits an emission
maximum at 732 nm with a high fluorescence quantum yield of 60% in
the wavelength range of 700–1000 nm and excellent photoblinking
without any additives. With resorcinol-functionalized PMIP (PMIP-OH), NIR SMLM imaging of lysosomes is demonstrated
for the first time in living mammalian cells under physiological conditions.
Moreover, metabolically labeled nascent DNA is site-specifically detected
using azido-functionalized PMIP (PMIP-N3) via click chemistry, thereby enabling the super-resolution
imaging of nascent DNA in phosphate-buffered saline with a 9-fold
improvement in spatial resolution. These results indicate the potential
of PMIP-based NIR blinking fluorophores for biological
applications of SMLM.