Ion Formation in MALDI

The mechanisms of ion formation in MALDI are a subject of continuing research. [30-34] The major concerns are the relationship between ion yield and laser flu-ence, [28,35] the temporal evolution of the desorption process and its implications upon ion formation, [36] the initial velocity of the desorbing ions, [29,37,38] and the question whether preformed ions or ions generated in the gas phase provide the major source of the ionic species detected in MALDI. [39,40]... 

Karas, M. KriigCT, R. Ion Formation in MALDI The Cluster Ionization Mechanism. Chem. Rev. 2003,103,427-439. 

Zenobi, R. and Knochenmuss, R., 1998, Ion formation in MALDI mass spectrometry, Mass Spectrom. Rev. 17 337-366. 

The mechanisms of ion formation in MALDI-MS are still not fully imder-stood. Two main possibilities exist ions may either be "pre-formed" in the solid state and simply be liberated upon laser irradiation, or they may be formed by ion-molecule reactions initiated by the laser pulse. ... 

Karas M, Kruger R. Ion formation in MALDI The cluster ionization mechanism. Chem Rev 2003 103 427-439. 

The mechanism of ion formation in MALDI is not completely understood however, it is known that ionization suppression effects must be taken into account if MALDI is to be used for quantitation. Also, above a certain concentration analyte signal cannot be increased... 

Zenobi R, Knochenmuss R. Ion Formation in MALDI mass spectrometry. Mass Spectrom Rev. 1998 17(5) 337-66. 

The mechanisms of ion formation in MALDI are a subject of continuing research [31-35]. The major concerns are the relationship between ion yield and laser flu-ence [26,36], the temporal evolution of the desorption process and its implications... 

Zenobi, R. Knochenmnss, R. Ion Formation in MALDI Mass Spectrometry. Mass Spectrom. Rev. 1999,17, 337-366. 

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