Bradykinin mass spectrum

FIGURE 4.4 MALDI-TOF mass spectrum acquired using a Voyager DE-STR (PerSeptive Biosystems) in linear mode of four peptides the mixture consisted of 1 pmole/ rL each of des-Arg -bradykinin, = 903.47 angiotensin I, = 1295.68 Glu-fibrin-... 

Figure 10.3 shows the IR-LDI mass spectrum of the peptide bradykinin (Mr = 1060.2) desorbed and ionized from the PDMS cover. The bradykinin was loaded into the chip at a concentration of 2.5 mM and injected into the chip channel using a field of 150 Y cm-1 for 9 min. The spectrum is the result of 10 laser shots at 2.95 pm wavelength. The off-line capillary gel microfluidic mass spectra are obtained after electrophoretic transport through a closed chip channel. Operation with a closed channel requires that the cover be removed from the chip prior to analysis. When removing the cover, sections of the gel tended to adhere to the surface of the PDMS. With some amount of care the entire gel lane could be extracted intact from the chip and, in many cases, irradiation of the PDMS cover resulted in the best mass spectra. The base peak... 

The PSD MALDI spectrum of Des-Arg1 bradykinine, whose sequence is PPGF-SPFR. The starred peaks correspond to the loss of a 28 Da fragment. Reproduced (modified) from Rouse J.C., Yu W. and Martin S.A., J. Am. Mass Spectrom., 6, 822-835, 1996, with permission. 

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