Figure 2

Plot Concentration/Area signal of ACTH standard peptide. It shows the plot of the area/concentration of a standard peptide (ACTH 18-39 clip, 2465.16 Da) after MALDI-MS analysis by 5000 shots/spot. We performed four replicated runs for each known concentration (5, 10 and 20 fmol/μl) of the standard peptide.