Facile Preparation of a Nanocomposite with Bifunctional Groups for the Separation and Analysis of Phosphopeptides in Human Saliva

Abstract

AbstractA composite material was well prepared (magCNT@PDA@NH2‐MIL‐125@mTiO2) with magnetic carbon nanotubes as a substrate and polydopamine as good hydrophilicity mid‐layer by facile procedure. Compared with single functional composite (magCNT@PDA@MIL‐125‐NH2 and magCNT@PDA@mTiO2), magCNT@PDA@NH2‐MIL‐125@mTiO2 exhibits higher sensitivity (4 fmol), better selectivity (nonphosphopeptides:phosphopeptodes=1 : 1000), as well as more excellent size‐exclusion effect towards phosphopeptides under the same conditions. Meanwhile, 33 phosphopeptides were selectively detected derived from human saliva, this result shows that the nanocomposite has the potential to enrich phosphopeptides from complex biological samples.