Delay Before Extraction to Improve Resolving Power

6 Delay Before Extraction to Improve Resolving Power 

Note Unfortunately, establishing patents and trademarks has caused redundant names for almost the same thing time lag focusing (TLF, Micromass) delayed extraction (DE, Applied Biosystems) pulsed ion extraction (PIE), and more recently panoramic pulsed ion extraction (PAN, Bruker Daltonik). 

Example Regardless of the manufacturer of the hardware, the effect of a time lag on resolution is quite dramatic. The resolving power of linear instruments is improved by a factor of 3-4 and reflector instruments become better by a factor of about 2-3 [44]. The advantages are obvious by comparison of the molecular ion signal of Ceo as obtained from a ReTOF instrument with continuous extraction (Fig. 4.7) and from the same instrument after upgrading with PIE (Fig. 4.11), or by examination of MALDI-TOF spectra of substance P, a low mass peptide, as obtained in continuous extraction mode and after PIE upgrade of the same instrument (Fig. 4.10). Modem mid-class MALDI-TOF instruments easily deliver twice that resolution. 

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