Selected Reaction Monitoring Applied to Quantitative Proteomics - LC-MS/MS in Proteomics: Methods and Applications - page 161

fragmentation patterns. Figure 9.2 shows an example of
co-eluting reference and endogenous peptides confidently
identified and presenting well-resolved HPLC traces which
will be retained for systematic quantitative assays. By spik-
ing the reference peptides at different concentration levels,
the LOD/LOQ and dynamic range of the peptides is estab-
lished by the addition of reference peptides to generate dilu-
tion curves, as illustrated in Fig. 9.3 .

GILFVGSGVSGGEEGAR LVEDPQVIAPFLGK

796.41 > 1062.48 763.43 > 561.34

801.41 > 1072.49

767.44 > 569.35

0 0

27.9 28.2 28.4

32.8 33.0 33.2

Fig. 9.2. SRM traces of the endogenous peptide and the internal standard.

2000000

1200

1600000

800

1200000

400

0

800000

0 20 40 60 80 100 [amol]

400000

0

0 20000 40000 60000 80000 100000 [amol]

GILFVGSGVSGGEEGA R 801.4 1072.5

LTILEEL R 498.8 782.5

LVEDPQVIAPFLG K 767.4 569.4

Fig. 9.3. Dilution curves (internal standards spiked into a yeast digest) demonstrating
the dynamic range of the technique.