COSAM » Departments » Chemistry & Biochemistry » Facilities » massspec » Learn about mass spectrometry » MALDI-TOF » Linear and Reflector
The instrument computer and software allowed the user to decide if they wanted to analyze their sample in linear mode or in reflectron mode.
Linear mode is preferable for large molecules (such as a whole protein) and consists of the ions traveling in a straight line from the source to the detector. The resolution of the instrument is limited due to different kinetic energies of the ions and variation in the start time from the laser desorption and ionization. The reflectron voltage is turned off when the instrument is operating in linear mode.
The reflectron improves the separation of the ions by normalizing their kinetic energies but the additional voltage can cause susceptible ions to fragment prematurely and not be detected.
Last Updated: 01/07/2020