Abstract: Objectives To further separate and identify the differentially expressed proteins analyzed by SELDI, and discuss the methodology significance. Methods Endothelial progenitor cells cultured in the medium adding with melatonin in concentration of 10μmol/L were used to extract proteins and analyze by SELDI for preliminary screening differentially expressed proteins. Tricine-SDS-PAGE and 2-DE was chosen to separate the target proteins, respectively, and FT-MS was used to identify the proteins. Results α-tubulin and human heat shock protein 90-α were detected by FT-MS after separated by Tricine-SDS-PAGE and 2-DE, respectively. Conclusion Tricine-SDS-PAGE is preferred for separating proteins in the mass range 35～62 ku, while 2-DE is better for separating bigger proteins.

Key words: SELDI, Tricine-SDS-PAGE, 2-DE, FT-MS