on 05-01-201210:45 AM - edited on 10-15-202111:42 AM by AnalyteGuru
Mæland Nilsen M, Uleberg KE, Janssen EA, Baak JP, Andersen OK, Hjelle A. J Proteomics. 2011 Nov 18;74(12):2995-8. SELDI-TOF MS has been demonstrated as a powerful tool for biomarker discovery. However, a major disadvantage of SELDI-TOF MS is the lack of direct identification of the discriminatory peaks discovered. We describe a novel experimental identification strategy where peptides/proteins captured to a weak cation exchange ProteinArray surface (CM10) are eluted, and thereafter identified by utilizing a sensitive LC–MS/MS (i.e. LTQ Orbitrap). A mixture of four known proteins was used to test the novel experimental approach described, and all four proteins were successfully identified. Additionally, a biomarker candidate previously discovered in plasma of Atlantic cod (Gadus morhua) by SELDI-TOF MS was identified. Thus, this study indicated that a combination of on-chip elution and a highly sensitive LC–MS/MS system can be an alternative approach to identify biomarker candidates discovered by use of SELDI-TOF MS.