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Title: Oxygen‐Sensing Chemiluminescent Iridium(III) 1,2‐Dioxetanes: Unusual Coordination and Activity
Abstract

Next generation chemiluminescent iridium 1,2‐dioxetane complexes have been developed which consist of the Schaap's 1,2‐dioxetane scaffold directly attached to the metal center. This was achieved by synthetically modifying the scaffold precursor with a phenylpyridine moiety, which can act as a ligand. Reaction of this scaffold ligand with the iridium dimer [Ir(BTP)2(μ‐Cl)]2(BTP=2‐(benzo[b]thiophen‐2‐yl)pyridine) yielded isomers which depict ligation through either the cyclometalating carbon or, interestingly, the sulfur atom of one BTP ligand. Their corresponding 1,2‐dioxetanes display chemiluminescent responses in buffered solutions, exhibiting a single, red‐shifted peak at 600 nm. This triplet emission was effectively quenched by oxygen, yielding in vitro Stern‐Volmer constants of 0.1 and 0.009 mbar−1for the carbon‐bound and sulfur compound, respectively. Lastly, the sulfur‐bound dioxetane was further utilized for oxygen sensing in muscle tissue of living mice and xenograft models of tumor hypoxia, depicting the ability of the probe chemiluminescence to penetrate biological tissue (total flux ∼106 p/s).

 
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Award ID(s):
2155170
NSF-PAR ID:
10381341
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Analysis & Sensing
Volume:
3
Issue:
1
ISSN:
2629-2742
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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