Pseudo-MS3 in a MALDI orthogonal quadrupole-time of flight mass spectrometer

Christina S. Raska, Carol E. Parker, Cai Huang, Jun Han, Gary L. Glish, Marshall Pope, Christoph H. Borchers

Результат исследований: Вклад в журналСтатьярецензирование

26 Цитирования (Scopus)


Both the matrix selected and the laser fluence play important roles in MALDI-quadrupole/time of flight (QqTOF) fragmentation processes. "Hot" matrices, such as α-cyano-4-hydroxycinnamic acid (HCCA), can increase fragmentation in MS spectra. Higher laser fluence also increases fragmentation. Typical peptide fragment ions observed in the QqTOF are a, b, and y ion series, which resemble low-energy CID product ions. This fragmentation may occur in the high-pressure region before the first mass-analyzing quadrupole. Fragment ions can be selected by the first quadrupole (Q1), and further sequenced by conventional MS/MS. This allows pseudo-MS3 experiments to be performed. For peptides of higher molecular weight, pseudo-MS3 can extend the mass range beyond what is usually accessible for sequencing, by allowing one to sequence a fragment ion of lower molecular weight instead of the full-length peptide. Peptides that predominantly show a single product ion after MS/MS yield improved sequence information when this technique is applied. This method was applied to the analysis of an in vitro phosphorylated peptide, where the intact enzymatically-generated peptide showed poor dissociation via MS/MS. Sequencing a fragment ion from the phosphopeptide enabled the phosphorylation site to be unambiguously determined.

Язык оригиналаАнглийский
Страницы (с-по)1034-1041
Число страниц8
ЖурналJournal of the American Society for Mass Spectrometry
Номер выпуска9
СостояниеОпубликовано - сент. 2002
Опубликовано для внешнего пользованияДа


Подробные сведения о темах исследования «Pseudo-MS3 in a MALDI orthogonal quadrupole-time of flight mass spectrometer». Вместе они формируют уникальный семантический отпечаток (fingerprint).