Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Sensing Mechanism and Excited-State Dynamics of a Widely Used Intracellular Fluorescent pH Probe : pHrodo

Jiang, Simin ; He, Yanmei LU ; Brandt, Jonas Højberg ; Zhao, Li LU and Chen, Junsheng LU (2023) In The Journal of Physical Chemistry Letters 14(46). p.10482-10488
Abstract
The pHrodo with an “off–on” response to the changes of pH has been
widely used as a fluorescent pH probe for bioimaging. The fluorescence
off–on mechanism is fundamentally important for its application and
further development. Herein, the sensing mechanism, especially the
relevant excited-state dynamics, of pHrodo is investigated by
steady-state and time-resolved spectroscopy as well as quantum chemical
calculations, showing that pHrodo is best understood using the
bichromophore model. Its first excited state (S1) is a charge transfer state between two chromophores. From S1, pHrodo relaxes to its ground state (S0) via an ultrafast nonradiative process (∼0.5 ps), which... (More)
The pHrodo with an “off–on” response to the changes of pH has been
widely used as a fluorescent pH probe for bioimaging. The fluorescence
off–on mechanism is fundamentally important for its application and
further development. Herein, the sensing mechanism, especially the
relevant excited-state dynamics, of pHrodo is investigated by
steady-state and time-resolved spectroscopy as well as quantum chemical
calculations, showing that pHrodo is best understood using the
bichromophore model. Its first excited state (S1) is a charge transfer state between two chromophores. From S1, pHrodo relaxes to its ground state (S0) via an ultrafast nonradiative process (∼0.5 ps), which causes its fluorescence to be “off”. After protonation, S1
becomes a localized excited state, which accounts for the fluorescence
being turned “on”. Our work provides photophysical insight into the
sensing mechanism of pHrodo and indicates the bichromophore model might
be relevant to a wide range of fluorescent probes. (Less)
Please use this url to cite or link to this publication:
author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
The Journal of Physical Chemistry Letters
volume
14
issue
46
pages
7 pages
publisher
The American Chemical Society (ACS)
external identifiers
  • scopus:85178545707
  • pmid:37967406
ISSN
1948-7185
DOI
10.1021/acs.jpclett.3c02653
language
English
LU publication?
yes
id
48445f2a-d289-4f8a-89ca-9f9875657158
date added to LUP
2024-05-03 10:25:49
date last changed
2024-05-18 06:28:45
@article{48445f2a-d289-4f8a-89ca-9f9875657158,
  abstract     = {{The pHrodo with an “off–on” response to the changes of pH has been <br>
widely used as a fluorescent pH probe for bioimaging. The fluorescence <br>
off–on mechanism is fundamentally important for its application and <br>
further development. Herein, the sensing mechanism, especially the <br>
relevant excited-state dynamics, of pHrodo is investigated by <br>
steady-state and time-resolved spectroscopy as well as quantum chemical <br>
calculations, showing that pHrodo is best understood using the <br>
bichromophore model. Its first excited state (S<sub>1</sub>) is a charge transfer state between two chromophores. From S<sub>1</sub>, pHrodo relaxes to its ground state (S<sub>0</sub>) via an ultrafast nonradiative process (∼0.5 ps), which causes its fluorescence to be “off”. After protonation,  S<sub>1</sub><br>
 becomes a localized excited state, which accounts for the fluorescence <br>
being turned “on”. Our work provides photophysical insight into the <br>
sensing mechanism of pHrodo and indicates the bichromophore model might <br>
be relevant to a wide range of fluorescent probes.}},
  author       = {{Jiang, Simin and He, Yanmei and Brandt, Jonas Højberg and Zhao, Li and Chen, Junsheng}},
  issn         = {{1948-7185}},
  language     = {{eng}},
  month        = {{11}},
  number       = {{46}},
  pages        = {{10482--10488}},
  publisher    = {{The American Chemical Society (ACS)}},
  series       = {{The Journal of Physical Chemistry Letters}},
  title        = {{Sensing Mechanism and Excited-State Dynamics of a Widely Used Intracellular Fluorescent pH Probe : pHrodo}},
  url          = {{http://dx.doi.org/10.1021/acs.jpclett.3c02653}},
  doi          = {{10.1021/acs.jpclett.3c02653}},
  volume       = {{14}},
  year         = {{2023}},
}