Open AccessNorcyanine-Carbamates Are Versatile Near-Infrared Fluorogenic Probes
Author(s) -
Syed Muhammad Usama,
Fuyuki Inagaki,
Hisataka Kobayashi,
Martin J. Schnermann
Publication year - 2021
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/jacs.1c02112
Subject(s) - cyanine , chemistry , chromophore , protonation , combinatorial chemistry , photochemistry , biodistribution , phototoxicity , fluorescence , carbamate , biophysics , biochemistry , in vitro , organic chemistry , ion , physics , quantum mechanics , biology
Fluorogenic probes in the near-infrared (NIR) region have the potential to provide stimuli-dependent information in living organisms. Here, we describe a new class of fluorogenic probes based on the heptamethine cyanine scaffold, the most broadly used NIR chromophore. These compounds result from modification of heptamethine norcyanines with stimuli-responsive carbamate linkers. The resulting cyanine carbamates (CyBams) exhibit exceptional turn-ON ratios (∼170×) due to dual requirements for NIR emission: carbamate cleavage through 1,6-elimination and chromophore protonation. Illustrating their utility in complex in vivo settings, a γ-glutamate substituted CyBam was applied to imaging γ-glutamyl transpeptidase (GGT) activity in a metastatic model of ovarian cancer. Overall, CyBams have significant potential to extend the reach of fluorogenic strategies to intact tissue and live animal imaging applications.