250
275
300
325
l (nm)
250
275
300
325
l (nm)
250
275
300
325
l (nm)
[M-6H] 6[M-4H] 4FragmentaƟon yield (arb. unit)
1
Electron detachment yield (arb. unit)
1
Electron detachment yield (arb. unit)
1
[Tyr+H] +
a
b
c
Fig. 8.4 Photofragmentation
yield of protonated tyrosine
[Tyr+H]
+ as a function of
laser wavelength (a).
Photodetachment yield as a
function of wavelength for the
gas-phase [M-4H]
4À (b) and
[M-6H]
6À (c) insulin ions.
Schematic structures of
tyrosine and insulin are given
in insets
8 UV–Visible Absorption Spectroscopy of Protein Ions
147