Direct Infusion Mass Spectrometry for Complex Lipid Analysis.Direct infusion or "shotgun" mass spectrometry provides a fast strategy to measure different classes of lipids, combining rapid analysis and short idle time.  Here we describe protocols for the quantification of the major plant glycerolipids (galactolipids, phospholipids, diacylglycerol, and triacylglycerol) using nanospray direct infusion mass spectrometry. 
Direct Infusion Mass Spectrometry
In contrast to liquid chromatography-mass spectrometry (LC-MS), the lipids are infused into the mass spectrometer without prior separation by liquid chromatography. 
liquid chromatography-mass spectrometry (LC-MS)
Ions are separated in the quadrupole of a tandem mass spectrometer, and after collision-induced dissociation fragments are quantified relative to internal standards in the third quadrupole or in the time-of-flight mass analyzer of a triple quadrupole or quadrupole time of flight (Q-TOF) mass spectrometer. 
tandem mass spectrometer
Ions are separated in the quadrupole of a tandem mass spectrometer, and after collision-induced dissociation fragments are quantified relative to internal standards in the third quadrupole or in the time-of-flight mass analyzer of a triple quadrupole or quadrupole time of flight (Q-TOF) mass spectrometer. 
triple quadrupole or quadrupole time of flight (Q-TOF) mass spectrometer