Identification of a single genome by electron paramagnetic resonance (EPR) with nitroxide-labeled oligonucleotide probes.

Nitroxide-labeled nucleic acids are used as a molecular size sensor to identify as few as one genome under polymerase chain reaction (PCR) conditions by electron paramagnetic resonance (EPR) spectroscopy. DNA identification is based on differences in the EPR spectra of mononitroxide-labeled nucleic acids. The experimental data imply that rapid DNA identification can be achieved in many systems by EPR at the molecular level.