Premium
Analysis of the differentially expressed low molecular weight peptides in human serum via an N‐terminal isotope labeling technique combining nano‐liquid chromatography/matrix‐assisted laser desorption/ionization mass spectrometry
Author(s) -
Leng Jiapeng,
Zhu Dong,
Wu Duojiao,
Zhu Tongyu,
Zhao Ningwei,
Guo Yinlong
Publication year - 2012
Publication title -
rapid communications in mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.528
H-Index - 136
eISSN - 1097-0231
pISSN - 0951-4198
DOI - 10.1002/rcm.6369
Subject(s) - chemistry , chromatography , mass spectrometry , peptide , matrix assisted laser desorption/ionization , matrix (chemical analysis) , protein mass spectrometry , isotope , isothiocyanate , desorption , analytical chemistry (journal) , tandem mass spectrometry , biochemistry , physics , organic chemistry , adsorption , quantum mechanics
RATIONALE Peptidomics analysis of human serum is challenging due to the low abundance of serum peptides and interference from the complex matrix. This study analyzed the differentially expressed (DE) low molecular weight peptides in human serum integrating a DMPITC‐based N‐terminal isotope labeling technique with nano‐liquid chromatography and matrix‐assisted laser desorption/ionization mass spectrometry (nano‐LC/MALDI‐MS). METHODS The workflow introduced a [ d 6 ]‐4,6‐dimethoxypyrimidine‐2‐isothiocyanate (DMPITC)‐labeled mixture of aliquots from test samples as the internal standard. The spiked [ d 0 ]‐DMPITC‐labeled samples were separated by nano‐LC then spotted on the MALDI target. Both quantitative and qualitative studies for serum peptides were achieved based on the isotope‐labeled peaks. RESULTS The DMPITC labeling technique combined with nano‐LC/MALDI‐MS not only minimized the errors in peptide quantitation, but also allowed convenient recognition of the labeled peptides due to the 6 Da mass difference. The data showed that the entire research procedure as well as the subsequent data analysis method were effective, reproducible, and sensitive for the analysis of DE serum peptides. CONCLUSIONS This study successfully established a research model for DE serum peptides using DMPITC‐based N‐terminal isotope labeling and nano‐LC/MALDI‐MS. Application of the DMPITC‐based N‐terminal labeling technique is expected to provide a promising tool for the investigation of peptides in vivo , especially for the analysis of DE peptides under different biological conditions. Copyright © 2012 John Wiley & Sons, Ltd.