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Desorption electrospray ionization (DESI) is an ambient ionization technique that can be coupled to mass spectrometry (MS) for chemical analysis of samples at atmospheric conditions. Coupled ionization sources-MS systems are popular in chemical analysis because the individual capabilities of various sources combined with different MS systems ...
Extractive electrospray ionization is a spray-type, ambient ionization method that uses two merged sprays, one of which is generated by electrospray. [ 49 ] Laser-based electrospray-based ambient ionization is a two-step process in which a pulsed laser is used to desorb or ablate material from a sample and the plume of material interacts with ...
Nanospray desorption electrospray ionization (nano-DESI) is an ambient pressure ionization technique used in mass spectrometry (MS) for chemical analysis of organic molecules. [1] In this technique, analytes are desorbed into a liquid bridge formed between two capillaries and the sampling surface. [ 2 ]
Schematic diagram of ion trap mass spectrometer with an electrospray ionization (ESI) source and Paul ion trap. A Paul trap is a type of quadrupole ion trap that uses static direct current (DC) and radio frequency (RF) oscillating electric fields to trap ions. Paul traps are commonly used as components of a mass spectrometer.
Electrostatic spray ionization (ESTASI) is an ambient ionization method for mass spectrometry (MS) analysis of samples located on a flat or porous surface, or inside a microchannel. It was developed in 2011 by Professor Hubert H. Girault ’s group at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland. [ 1 ]
The chemical ionization process generally imparts less energy to an analyte molecule than does electron impact (EI) ionization, resulting in less fragmentation [2] and usually a simpler spectrum. The amount of fragmentation, and therefore the amount of structural information produced by the process can be controlled to some degree by selection ...
[13] [9] [2] In addition to the source geometry optimization, the electrospray solvent composition has an effect on the MALDESI signals (i.e. influencing molecular coverage and ion abundance). In a study to improve the detection of tissue-specific lipids, the electrospray parameters have been tailored for positive and negative ionization ...
Ionization energy is positive for neutral atoms, meaning that the ionization is an endothermic process. Roughly speaking, the closer the outermost electrons are to the nucleus of the atom, the higher the atom's ionization energy. In physics, ionization energy (IE) is usually expressed in electronvolts (eV) or joules (J).