Like other mass spectrometry methods, TOF-MS can analyze ions based on their mass-to-charge ratio. The sample to be analyzed is separated by liquid chromatography, similar to HPLC, and then the eluted molecules enter the interface so that the mobile phase can be removed before entering the mass spec detector.
Time-of-flight mass spectrometry utilizes a vacuum chamber. Ions are accelerated through the chamber by an electric field but once they enter the chamber there is no electric field and the ions move only by the kinetic energy obtained when they were originally accelerated. Heavier ions of the same charge as move slower and therefore reach the detector later then smaller ions with the same charge. Based on the time it takes for ions to move from one end of the chamber to the other can be used to calculate their mass-to-charge ratios.
Pacific BioLabs has a SciEx TripleTOF 5600 High Resolution Mass Spec System which is capable of generating high resolution data allowing tentative identification of compounds even at very small concentrations. Read more about PBL’s TripleTOF on our blog.