Evaluating rapid evaporative ionization mass spectrometry profiles of human breast cancer cells using a 3D in vitro assay.

Rapid evaporative ionization mass spectrometry (REIMS) enables near real-time sampling and classification of tissues on the basis of lipid and small molecule profiles. Because samples are ablated during REIMS, validation of mass spectra by assignment of class labels using gold-standard methods remains challenging. Further, determining the number of abnormal cells within a mixture of normal cells by REIMS remains an elusive but critical parameter when evaluating the utility of REIMS for use in clinical settings.