Zirconium Phosphonate-Modified Porous Silicon for Highly Specific Capture of Phosphopeptides and MALDI-TOF MS Analysis
- Resource Type
- Article
- Authors
- Zhou, Houjiang; Xu, Songyun; Ye, Mingliang; Feng, Shun; Pan, Chensong; Jiang, Xiaogang; Li, Xin; Han, Guanghui; Fu, Yu; Zou, Hanfa
- Source
- Journal of Proteome Research; September 2006, Vol. 5 Issue: 9 p2431-2437, 7p
- Subject
- Language
- ISSN
- 15353893; 15353907
Phosphorylation is one of the most important post-translational modifications of proteins, which modulates a wide range of biological functions and activity of proteins. The analysis of phosphopeptides is still one of the most challenging tasks in proteomics research by mass spectrometry. In this study, a novel phosphopeptide enrichment approach based on the strong interaction of zirconium phosphonate (ZrP) modified surface with phosphopeptides has been developed. ZrP modified porous silicon (ZrP-pSi) wafer was prepared to specifically capture the phosphopeptides from complex peptide mixtures, and then the captured phosphopeptides were analyzed by MALDI-TOF MS by directly placing the wafer on a MALDI target. The phosphopeptide enrichment and MALDI analysis were both performed on the ZrP-pSi wafer which significantly reduced the sample loss and simplified the analytical procedures. The prepared ZrP-pSi wafer has been successfully applied for the enrichment of phosphopeptides from the tryptic digest of standard phosphoproteins -casein and -casein. The excellent selectivity of this approach was demonstrated by analyzing phosphopeptides in the digest mixture of -casein and bovine serum albumin with molar ratio of 1:100. High detection sensitivity has been achieved for the analysis of the phosphopeptides from tryptic digestion of 2 fmol -casein on the ZrP-pSi surface.