By tuning in on the spin of unpaired electrons, scientists are finding new characteristic differences between normal and malignant tissue.
In addition, research results suggest that the technique may enable investigators to spot a pre-neoplastic change in tissue.
The method of measurement is electron spin resonance spectroscopy ( ESR), first developed in 1946 in physics laboratories for the study of the unpaired electron of a fragment of a molecule or atom, and adapted more recently for biochemical research.
Unpaired or "free" electrons are the identifying signature of free radicals, the highly reactive, shortlived molecule fragments which in theory play an important role in the chemical reactions in tissue rapidly undergoing change in character. As a result of this association between unpaired electrons and free radicals, it is possible to detect and analyze free radicals by ESR— thus creating a new window through which to view tissue changes.
A major advantage of