Mesoporous Zirconium Phenylphosphonates for Selective Enrichment of Phosphopeptides

Mesoporous zirconium phenylphosphonates were synthesized by one-pot co-condensation of ZrCl 4 and phenylphosphonic acid (PPA) under weak acidic medium using sodium dodecyl sulfate (SDS) as a template. The structure and chemical states of the synthesized materials were characterized by N 2 sorption, powder XRD, TEM and FT-IR, ICP, and solid-state NMR, indicating that the hybrids possess mesoporous structure and the frameworks are constructed by the coordination of zirconium(IV) with phenylphosphonates. These mesoporous materials present a considerable amount of uniformly distributed zirconium(IV) throughout the frameworks available for the enrichment of phosphopeptides, which causes them to circumvent the complex preloading of metal ions required for traditional immobilized metal affinity chromatographic (IMAC) adsorbents. Thus, the materials are first applied as IMAC adsorbents to enrich phosphopeptides from the tryptic digests of both standard phosphoproteins and a mixture of proteins. MALDI-TOF MS analysis shows that mesoporous zirconium phenylphosphonates exhibit satisfying efficiency and specificity in the enrichment of phosphopeptides from peptides even under strong interference of nonphophopeptides.