Soft-template synthesis of hydrophilic metallic zirconia nanoparticle-incorporated ordered mesoporous carbon composite and its application in phosphopeptide enrichment

Abstract

Novel nanostructure metallic zirconia incorporated ordered mesoporous carbon (OMC) composites were synthesized via a multi-component co-assembly strategy associated with a direct carbonization process from resol, ZrO(NO₃)₂·xH₂O, and triblock copolymer F127. Herein, the novel metallic zirconia incorporated OMC as a Metal Oxide Affinity Chromatography (MOAC) material had large mesopores (5.6 nm), a high surface area (387 m² g⁻¹), a large pore volume (0.35 cm³ g⁻¹) and excellent hydrophilicity for the selective enrichment of phosphopeptides. The surface construction and chemical composition of the material were characterized by SEM, TEM, XPS, EDS, BET, and XRD. Experimental conditions for trapping phosphopeptides were optimized using β-casein as the standard protein. Under the optimal conditions combined with the merits of high surface area of material and special combination with phosphopeptides, the zirconia/OMC composites for enrichment of the phosphopeptides showed a high selectivity (phosphopeptides/non-phosphopeptides at a molar ratio of 1 : 300) and lower detection sensitivity (1.5 fmol). Moreover, the as-prepared MOAC zirconia/OMC composites were successfully applied to the detection and identification of low-abundance phosphopeptides from non-fat milk.