The method is based on putting a plant cell in a glass capillary with metallic coating on a nanospray chip and aspirating intracellular components or subcellular organelles. By introducing ionized organic solvent from the rear end of the chip and placing the chip in the vicinity of the sample introduction port of the mass spectrometer, molecules in the sample are ionized and introduced into the mass spectrometer. Hundreds to thousands ionized molecules can be detected within minutes.
RIKEN news release, August 28, 2015
RIKEN team develops direct metabolomic assay for plant single cells by live single cell mass spectrometry