Matrix Assisted Laser Desorption/Ionization-Mass Spectrometry : MALDI-MS

Principle

By irradiating a homogeneous mixture of a sample and a large excess of a matrix reagent (a compound that absorbs the energy of an N2 laser at a wavelength of 337 nm) with a laser, the matrix reagent first absorbs the energy. The absorbed energy causes the matrix reagent to vaporize with the surrounding sample molecules, and the vaporized sample molecules are ionized by the addition of protons and cations. In the case of neutral compounds, a cationic agent may be added to accelerate the ionization process.