Post curved field reflectrons

Both collisional activation (in ion traps) and post source decay (in curved field reflectron TOF analyzers) have been used successfully to obtain sequence ions from peptides prepared in situ on the sample holder. Single Dalton mass windows are advantageous for precursor selection, as are realized in ion-trap and trap-TOF configurations. Publicly available search algorithms can be used... 

Cordero, M.M. Cornish, T.J. Cotter, R.J. Lys, LA. Sequencing Peptides Without Scanning the Reflectron Post-Source Decay With a Curved-Field Reflectron TOF Spectrometer. Rapid Commun. Mass Spectrom. 1995, 9, 1356-1361. 

Cordero MM, Cornish TJ, Cotter RJ, and Lys lA (1995) Sequencing peptides without scanning the reflectron post-source decay with a curved-field reflectron time-of-flight mass spectrometer. Rapid Communications in Mass Spectrometry 9 1356-1361. 

FIGURE 8.24 Post-source decay mass spectrum of the peptide (Pro) 4Arg obtained using a curved-field reflectron and used for mass calibration. (Reprinted with permission from reference 15)... 

Some Examples. Earlier in this chapter, we discussed the isolation and identification of an antigen AMAPBTLLL bound to a novel murine Class IB MHC molecule Qa-1. In that example, the amino acid sequence was determined from the MALDI mass spectra of ladder peptides obtained from aminopeptidase M, carboxypeptidase P, and chymotrypsin digestions. As shown in Figure 10.19, the amino acid sequence can also be determined from the post-source decay MALDI mass spectrum of the intact peptide. In this case, a curved-field reflectron was used, so that the entire mass spectrum was recorded without changing the reflectron voltage. 

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