The development of new methods for ionization of complex molecular structures is ever present due to the wide application of mass spectrometry. UVPD (ultraviolet photodissociation) excites ions by absorption of high-energy photons, which opens up new dissociation paths compared to conventional methods of ion activation. Specifically, this means using shorter wavelengths, such as 266 nm (4.6 eV) or 213 nm (5.8 eV), whose single photons have energies higher than 355 nm (3.5 eV).
Mass spectrometry is used in many different fields, e.g. in pharmacology and for the characterization of proteins or aerosols, and is applied to pure samples as well as to complex mixtures. Laser-based generation of ions has been dominated by excimer and nitrogen lasers for decades and is becoming increasingly important in medicine, food technology and pharmaceuticals. Gas lasers are gradually and partially being replaced by diode-pumped solid-state lasers.