Open AccessOxymetry deep in tissues with low-frequency electron paramagnetic resonance.
Author(s) -
Howard J. Halpern,
Yu Cheng,
Miroslav Perić,
Eugene D. Barth,
David J. Grdina,
Beverly A. Teicher
Publication year - 1994
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.91.26.13047
Subject(s) - electron paramagnetic resonance , hypoxia (environmental) , oxygen , chemistry , nuclear magnetic resonance , compartment (ship) , tumor hypoxia , biophysics , radiochemistry , pathology , radiation therapy , medicine , biology , physics , oceanography , organic chemistry , geology
We have measured the oxygen concentration in the body water of murine FSa and NFSa fibrosarcomas using a new method for quantitative oxygen concentration determination deep in the tissues of a living animal. The measurement uses unusually low-frequency electron paramagnetic spectroscopy sensitive to substrate 7 cm deep in tissue, partially deuterated spin probes (spin labels of molecular mass 195, approximating that of glucose) whose distribution compartment can be targeted with facile adduct substitution, and novel analytic techniques. We show that the water-compartment oxygen concentration of the tumors decreases as the tumor size increases and also shows a trend to decrease as radiobiologic hypoxia increases. An oxymetric spectral image of the tumor is presented. The technique will improve with larger human tissue samples. It provides the potential to quantitatively assess tissue hypoxia in ischemic or preischemic states in stroke and myocardial infarction. It will allow direct assessment of tumor hypoxia to determine the usefulness of radiation and chemotherapy adjuvants directed to hypoxic cell compartments.