C.W. Tsao, W.Y. Chen, C.H. Lin, Y.C. Cheng
National Central University, Taiwan
pp. 34 - 38
Keywords: desorption/ionization on silicon, nanostructured silicon, magnetic nanoparticle, mass spectrometry
Stem cells can differentiated into various cell types which can be used to repair damage organs in regenerative medicine applications. The cell regulation process such as cell division, differentiation, and apoptosis are deeply related to protein phosphorylation in cell transduction pathway. However, low abundance of phosphorylated peptides and proteins in cell makes identification of phosphorylation sites difficult. Therefore, developing a rapid, high performance analytical tool to analysis phosphopeptide is important in tissue engineering or other related fields. Mass spectrometry (MS) is a widely used tool to analysis biomolecules. In recently year, desorption/ionization on silicon (DIOS) have been proposed as high sensitivity MS analysis approach. In this presentation, we demonstrate using nanostructured silicon (nSi) as DIOS substrate and coupled with functionalized ioron oxide magnetic nanoparticles (MNPs) for phosphopeptide analysis. Phosphopeptide derived from β-casein digest has also been successfully detected by nSi incorporated with Fe3O4/TiO2 and Fe3O4/ZnO MNPs (nSi-MNPs). High detection sensitivity as high as 10-9 M level can be achieved by nSi-MNPs approach. Results show that nSi-MNPs technique is a high performance approach for phosphopeptide analysis where nSi service as DIOS-MS target substrate for high detection sensitivity and MNPs selectively capture the phosphopeptide for enhanced detection selectivity.