Dendritic Mesoporous Silica Nanoparticles with Abundant Ti for Phosphopeptide Enrichment from Cancer Cells with 96% Specificity.

Selective enrichment and sensitive detection of phosphopeptides are of great significance in many bioapplications. In this work, dendritic mesoporous silica nanoparticles modified with polydopamine and chelated Ti (denoted DMSNs@PDA-Ti) were developed to improve the enrichment selectivity of phosphopeptides. The unique central-radial pore structures endowed DMSNs@PDA-Ti with a high surface area (362 m g), a large pore volume (1.37 cm g), and a high amount of chelated Ti (75 μg mg). Compared with conventional mesoporous silica-based materials with the same functionalization (denoted mSiO@PDA-Ti) and commercial TiO, DMSNs@PDA-Ti showed better selectivity and a lower detection limit (0.2 fmol/μL). Moreover, 2422 unique phosphopeptides were identified from HeLa cell extracts with a high specificity (>95%) enabled by DMSNs@PDA-Ti, better than those in previous reports.