Laser ablation electrospray ionization

Note In order to minimize the interference of external electromagnetic fields and air currents the LAESI system is shielded by a Faraday cage and a plastic enclosure, respectively. The enclosure also provides protection from potential health hazards of the fine particulates generated in the laser ablation process. 

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Laser ablation electrospray ionization mass spectrometry Laser ablation-inductively coupled plasma-mass spectrometry... 

The ionization methods reported for IMS included MALDI [41,76-80], Secondary Ion Mass Spectrometry (SIMS) [19, 81-86], Matrix-enhanced (ME)-SIMS [87, 88], Desorption Electrospray Ionization (DESI) [89-99], Nanostructure Initiator Mass Spectrometry (NIMS) [100-102], Atmospheric Pressure Infrared MALDI Mass Spectrometry (AP-IR-MALDI-MS) [103], Laser Ablation-inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) [104-106], Laser Desorption Postionization (LDPI) [107], Laser Ablation Electrospray Ionization Mass Spectrometry (LAESI) [108, 109], and Surface-assisted Laser Desorption/ioniza-tion Mass Spectrometry (SALDI) [110-112], Another method was called probe electrospray ionization (PESI) that was used for both liquid solution and the direct sampling on wet samples. 

Nemes P, Barton A, Li Y, Vertes A (2008) Ambient molecular imaging and depth profiling of live tissue by infrared laser ablation electrospray ionization mass spectrometry. Anal Chem 80 4575 1582. doi 10.1021/ac8004082... 

Nemes P, Woods A, Vertes A (2010) Simultaneous imaging of small metabolites and lipids in rat brain tissue at atmospheric pressure by laser ablation electrospray ionization mass spectrometry. Anal Chem 82 982-988. doi 10.1021/ac902245p... 

Laser ablation electrospray ionization (LAESI) is especially designed for biological samples containing water. Using this technique, a focused mid-IR laser excites the OH vibrations in a sample s water molecules. Phase explosion causes a rapid microscale ablation, ejecting a mixture of molecules, clusters, and particulate matter from the sample surface. Variations in the water content... 

Several other ionization methods have been developed based on DESI, including desorption atmospheric pressure chemical ionization (DAPCI), desorption atmospheric pressure photo-ionization (DAPPI), laser ablation electrospray ionization (LAESI), and extractive electrospray ionization (EESI). Each technique uses variations of the solvent, how the charged beam is formed, and how the beam is nsed to facilitate the prodnction of analyte ions. Because these are surface methods (except EESI), they are incompatible with LC. 

Nemes P, Vertes A. Laser ablation electrospray ionization for atmospheric pressure, in vivo, and imaging mass spectrometry. Anal Chem 2007 79 8098-8106. 

HA-LAESI heat-assisted laser ablation electrospray ionization HR-EI high-resolution electron impact... 

Nemes, P, Vertes, A. (2007) Laser Ablation Electrospray Ionization for Atmospheric Pressure, In Vivo, and Imaging Mass Spectrometry. Anal. Chem. 79 8098-8106. 

Probe electrospray ionization (PESI) and TOF-MS were used for direct profiling of phytochemicals in different parts of a fresh tulip bulb [80], which emphasized the possibility of conducting in-vivo MS analysis of less sensitive biological matrices such as plant tissues. Recently, Pan et al. [81] demonstrated single-probe MS which can conduct metabolomic analysis of individual living cells in real time. The diameter of this probe is < 10 pm which makes the device compatible with eukaryotic cells. Atmospheric pressure ion sources are particularly suitable for analysis of live biological specimens. Cellular metabolism does not need to be quenched before analysis. For instance, in laser ablation electrospray ionization (LAESI)-MS, cells are irradiated by a laser beam in order to extract small amounts of cytosolic components, and to transfer them to the ESI plume [82]. 

Laser Ablation Electrospray Ionization for Atmospheric Pressure Molecular Imaging Mass Spectrometry... 

Nemes, R, Barton, A. A., Vertes, A. (2009) Three-dimensional imaging of metabolites in tissues imder native conditions by laser ablation electrospray ionization mass spectrometry. Anal Chem, 81, 6668-6675. 

LAESI Laser ablation electrospray ionization IR laser ablation with postionization by ESI plume [53]... 

A. Ambient Molecular Imaging and Depth Profiling of Live Tissue by Infrared Laser Ablation Electrospray Ionization Mass Spectrometry. Anal. Chem. 2008,50,4575-4582. 

Sripadi, P. Nazarian, J. Hathout, Y. Hoffman, E.P. Vertes, A. In Vitro Analysis of Metabolites from the Untreated Tissue of Torpedo Califomica Electric Organ by Mid-Infrared Laser Ablation Electrospray Ionization Mass Spectrometry. Metaholomics 2009, 5, 263-276. 

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