1: J Magn Reson. 2009 Apr;197(2):176-80. Epub 2008 Dec 24.

Nano-emulsions of fluorinated trityl radicals as sensors for EPR oximetry.

Charlier N, Driesschaert B, Wauthoz N, Beghein N, Préat V, Amighi K,
Marchand-Brynaert J, Gallez B.

Université catholique de Louvain, Laboratory of Biomedical Magnetic Resonance,
REMA, Brussels, Belgium.

This article reports the development and evaluation of two nano-emulsions
(F45T-03/HFB and F15T-03/PFOB) containing fluorinated trityl radicals dissolved
in perfluorocarbons. Preparation with a high-pressure homogenizer conferred
sub-micronic size to both nano-emulsions. In vitro and in vivo EPR spectroscopy
showed that the nano-emulsions had much greater oxygen sensitivity than the
hydrophilic trityl, CT-03. In vivo experiments in rodents confirmed the ability
of the nano-emulsions to follow the changes in oxygen concentration after induced
ischemia. Histological evaluation of the tissue injected with the nano-emulsions 
revealed some acute toxicity for the F45T-03/HFB nano-emulsion but none for the
F15T-03/PFOB nano-emulsion. These new formulations should be considered for
further EPR oximetry experiments in pathophysiological situations where subtle
changes in tissue oxygenation are expected.


PMID: 19128993 [PubMed - in process]

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