Translational diffusion heterospecies , line broadening, and saturation

The interaction between nitroxides and oxygen has been used as a basis for measurement of dissolved oxygen, a procedure that may be termed spin-label oximetry. In this approach calibration curves are constructed relating a nitroxide 

Hyde and Sarna [43] showed that when spin labels collide with fast relaxing paramagnetic species, Heisenberg exchange provides a thermal contact between the slow relaxing species and the lattice. Thus, there is a change in effective This effect has been observed directly by Kusumi et al. [42]. 

Heisenberg exchange between and labeled species is an ELDOR-active process, and ELDOR with can be used with great precision to investigate 

The reader is referred to the distinguished book by Molin et al. [16], on exchange interactions in ESR spectroscopy. 

Schreier and her colleagues have described the use of spin labels with weakly interacting protons that have pK values near 7 as pH indicators [29]. 

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