Monitoring the neuropeptide metabolites by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
The developments of bio-analytical methods for analyzing bioactive peptides are of paramount importance. Neuropeptides and their bioactive fragments play a vital role in the regulation of many biological processes and diseases. This paper presents the use of matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) method for monitoring neuropeptides along with their degradation products in plasma samples from cancer patients. The neuropeptides focused in this study were beta-endrophin, substance P, and bradykinin. The method involves the enzyme digestion of the neuroactive peptides followed by MALDI-MS sample preparation and subsequent acquisition of the MS spectral data. The mass spectral profile identifies most of the C-terminal and N-terminal peptides, and the mass accuracy was in the range of -1.68 to 1.46 Da with the mass spectrometer utilised. Analysis of the neuropeptide degradation patterns from the cancer patients were compared with the controls showed similar results. The study reveals that this approach can be used to identify the enzymatic digestion products of protein.
Babu
C V Suresh
CV
Bioanalysis and Biotransformation Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, Republic of Korea.
Lho
Dong Seok
DS
Yoo
Young Sook
YS
D001920:Bradykinin / Q000032:analysis; D018826:CD13 Antigens / Q000032:analysis; D043402:Cathepsin A / Q000032:analysis; D002623:Chemistry Techniques, Analytical / Q000379:methods; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D019075:Electrophoresis, Capillary; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D009369:Neoplasms / Q000378:metabolism; D009479:Neuropeptides / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D017434:Protein Structure, Tertiary; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014357:Trypsin / Q000032:analysis / Q000737:chemistry; D001615:beta-Endorphin / Q000032:analysis
D009479:Neuropeptides; D010455:Peptides; D001615:beta-Endorphin; D018826:CD13 Antigens; D043402:Cathepsin A; D014357:Trypsin; D001920:Bradykinin