Methodology Report

Enhanced MALDI-TOF MS Analysis of Phosphopeptides Using an Optimized DHAP/DAHC Matrix

Figure 5

Tryptic digests of 𝛼 - (upper) and 𝛽 -casein (lower) (12.5–250 fmol on target) were detected with DHAP/DAHC (a) and (c) and DHB/PA (b) and (d) by MALDI-TOF MS in positive mode. DHAP/DAHC positions were selected randomly in the outer ring of the sample; for DHB/PA, only signals in hot spots were collected. In total, 200 profiles were accumulated for each sample. The number of sites on each phosphopeptide was equal to the number of asterisks ( ).
759690.fig.005a
(a)
759690.fig.005b
(b)
759690.fig.005c
(c)
759690.fig.005d
(d)