Comparison of peptide standard solution before (top) and after (bottom) FaRP immunoprecipitation. The peptide standard solution prepared in binding/wash buffer contained 10-6 M of the following peptides: FMRF amide-like peptide I, lobster (m/z 1053.5588, SDRNFLRFa), bradykinin (m/z 1060.5687, RPPGFSPFR), FMRF amide-like peptide II, lobster (m/z 1066.5905, TNRNFLRFa), and substance P (m/z 1347.7354, RPKPQQFFGLMa). IP elution reveals selective enrichment and detection of two FaRP peptides.