Figure 3.
Comparison of two neuropeptide extraction methods followed by the two purification methods by MALDI-FTMS as well as by DiLeu. Four lobster brains of similar sizes are processed in the order of solvent extraction (acidified methanol or DMF) and desalting (Beads or Ziptip). Profiling of neuropeptides extracted by (a-b) acidified methanol and (c-d) DMF. The desalting methods are magnetic beads for (a) and (c) and Ziptip for (b) and (d), respectively. The above four spectra have been adjusted to the same intensity scale. (e) The cleaned samples were labeled by DiLeu as shown. (f) Quantitation of reporter ions for one peptide VYGPRDIANLY (m/z 1280.66) comparing the above four methods in combination.