Development of nitroxides for selective localization inside cells

doi:10.1016/0167-4889(89)90214-0

Biochimica et Biophysica Acta (BBA) - Molecular Cell Research

Volume 1014, Issue 3, 14 December 1989, Pages 211-218

https://doi.org/10.1016/0167-4889(89)90214-0 Get rights and content

Abstract

The use of nitroxides to measure intracellular phenomena, especially oxygen concentrations, is a new and potentially important approach to a number of physiological and pathophysiological studies. This study provides data indicating the feasibility of developing nitroxides that localize selectively in the intracellular compartment; it is based on the use of readily hydrolysed ester linkages, such that the nitroxides become converted intracellularly to ionic derivatives that do not cross cell membranes readily. Up to 120-fold increased concentrations of intracellular nitroxides (and their one electron reduction product, the hydroxylamines) were obtained. The ESR spectra of the intracellular nitroxides were consistent with their conversion to the ionic species. Preliminary studies indicate that these nitroxides have the properties needed for their use as probes of intracellular concentrations of oxygen and that it should be feasible to synthesize nitroxides that will be even more effective for this purpose.

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^*: Present address: Department of Chemistry, Illinois State University, Normal, IL 61761, U.S.A.

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Development of nitroxides for selective localization inside cells

Abstract

Biophys. J.

Arch. Biochem. Biophys.

Biochim. Biophys. Acta

J. Biol. Chem.

Biochim. Biophys. Acta

Biochim. Biophys. Acta

J. Am. Chem. Soc.

Magnetic Resonance in Medicine

J. Cell. Physiol.

J. Magn. Reson. Med. and Biol.