Carbon based paramagnetic materials are frequently used for EPR oximetry, especially in vivo, but the EPR spectra of these materials often show more than one paramagnetic center and/or relatively low signal intensity. To determine whether the components of carbon based materials could be separated and enriched in the active component, we used density gradient centrifugation to separate the materials into several fractions. We studied two types of coals, gloxy and Pocahontas, and found these materials to have large density distribution. The separated density fractions had very different EPR spectra and intensities. The active component from the coal material displays a more homogeneous EPR signal, and significantly increased EPR signal intensity. In similar studies with India ink, only slight changes were observed in attempts to separate the material. These results with coals may be very useful in the development of better probes for EPR oximetry.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR011602-04
Application #
6206518
Study Section
Project Start
1999-09-01
Project End
2000-08-31
Budget Start
1998-10-01
Budget End
1999-09-30
Support Year
4
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Dartmouth College
Department
Type
DUNS #
041027822
City
Hanover
State
NH
Country
United States
Zip Code
03755
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