A contamination-insensitive probe for imaging specific biomolecules by secondary ion mass spectrometry.

Imaging techniques should differentiate between specific signals, from the biomolecules of interest, and non-specific signals, from the background. We present a probe containing (15)N and (14)N isotopes in approximately equal proportion, for secondary ion mass spectrometry imaging. This probe designed for a precise biomolecule analysis is insensitive to background signals.