ISSN:
0951-4198
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Physics
Notes:
Sequential daughter-ion-scanning analyses of small peptides have been performed using a hybrid tandem instrument of BEqQ configuration. Precursor ions are selected by B and allowed or induced (by high-energy collisional activation) to decompose in the region preceding E. Decoupling of E from the accelerating voltage permits the selection of the first-generation daughter ion whilst retaining appropriate float voltages for the quadrupole assemblies. The daughter ion selected by E is further subjected to low-energy collisional-activation dissociation (CAD) in q and the fragment-ion spectrum is obtained by scanning Q. The sequential daughter-ion-scanning technique has been used to establish that ‘internal’ fragments of the types, (AY′) and (BY′), are formed via initial Y-type cleavage. Fragmentation of a protonated peptide (angiotensin III) by loss of the C-terminal amino acid residue, yielding a (Bn′ + OH) ion, is reported for the first time. This process is analogous to that previously described for metal-cationized peptides.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/rcm.1290030704