MALDI

Matrix Assisted Laser Desorption Ionization is a soft ionization technique used in mass spectrometry which allows the analysis of many types of molecules, such as biomolecules (peptides, proteins, sugars) and large organic molecules (polymers). A laser beam is directed at a matrix/sample mix that is co-crystallized on a metallic surface. The laser beam desorbs and ionizes the mix. The matrix absorbs the energy from the laser, becomes stimulated, ionizes, and changes to a gaseous state. The expansion of the matrix induces the sample to transform into a gas as well; the latter also ionizes. The matrix is a small molecule capable of forming crystals with the sample and of rapidly absorbing the energy from the laser, which protects the sample.