Fabrication of a novel magnetic yolk–shell Fe3O4@mTiO2@mSiO2 nanocomposite for selective enrichment of endogenous phosphopeptides from a complex sample

A yolk-shell nanocomposite composed of a magnetic mesoporous anatase TiO2 (Fe3O4@mTiO(2)) core, a medium cavity and an outermost mesoporous silica (mSiO(2)) shell was successfully fabricated. Due to a combination of the strong magnetic response, improved diffusion of peptides, numerous affinity sites towards phosphopeptides and the size-exclusion effect, the nanocomposite demonstrated high enrichment efficacy and selectivity towards endogenous phosphopeptides from human serum.