Electrospray generation

The present description is based on previous publications from this laboratory56-59 and the interested reader will find additional details and references in that work. Two different ion-source reaction chambers are used. One of these sources which operates at room temperature is shown in Figure 4. The second source, a variable temperature source will also be described. The electrospray generator and the ion-source reaction chamber are shown in Figure 4, while the mounting of the ion source and the front end of the mass spectrometer are shown in Figure 5. 

The desirability to obtain thermochemical information on ion-ligand interactions in complexes, M2+Ln, involving alkaline earth and transition metal M2+ ions was one of the principle aims which led to the development of apparatus for electrospray generated ions.70 Unfortunately only modest progress has been achieved so far. 

Cuyckens F and Claeys M. 2005. Determination of the glycosylation site in llavonoid mono-O-glycosides by collision-induced dissociation of electrospray-generated deprotonated and sodiated molecules. J Mass Spectrom 40(3) 364-372. 

Guevremont R, Ding L, Ells B, Barnett DA, Purves RW (2001) Atmospheric pressure ion trapping in a tandem FAIMS-FAIMS coupled to a TOFMS studies with electrospray generated gramicidin S ions. J Am Soc Mass Spectrom 12(12) 1320-1330... 

The first mode to interface the sample effluent from a microchip to a mass spectrometer (MS) was based on electrospray ionization (ESI). For electrospray generation, a sharp tip is usually used as an emitter. For instance, a sheath flow micro-ion sprayer was used to interface a microchip to a mass spectrometer (see Figure 7.30). CE separation was first carried out, and then the separated components were transferred to the mass spectrometer for MS analysis [812]. 

Electrospray Generation of charged Ionization directly from sample solution... 

Figure 7.7 Image of a zero dead-volume microfluidic channel-capillary junction for electrospray generation. (Reprinted with permission from ref. 36).

Electrospray Generation from Capillary Emitters Inserted in the Chip... 

Chu, I.K. Rodriguez, C.F. Hopkinson, A.C. Siu, K.W.M. Lau, T.-C. Formation of molecular radical cations of enkephahn derivahves via coUision-induced dissociation of electrospray-generated copper(II) complex ions of amines and pephdes. J. Am. Soc. Mass Spectrom. 2001, 72, 1114-1119. 

Figure 8. (A) Schematic diagram of microchip used to pump fluids electroosniotically and to generate the electrospray (B) Photomicrograph of the Taylor cone and electrospray generated from a 60% H2O-40% methanol solution that was electroosniotically pumped using a microchip (reproduced from Ramsey [51])...

Guevremont, R. Sin, K. W. M. Wang, J. Y. Ding, L. Y. Combined ion mobility time-of-flight mass spectrometry study of electrospray-generated ions. Analytical Chemistry 1997, 69, 3959-3965. 

Zhu, j. Cole, R. B. Ranking of gas-phase acidities and chloride affinities of monosaccharides and linkage specificity in collision-induced decompositions of Negative Ion Electrospray-Generated chloride adducts of oligosaccharides. J. Am. Soc. Mass Spectrom. 2001, 12, 1193-1204. 

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