A number of improved methods based on polymer brush or network have been reported [19,20]. The glycoprotein/glycopeptide could react with soluble polymer sidechain in a homogeneous aqueous system to avoid the mass transport limitations inherent in chromatography strategy. Moreover, the thermoresponsible polymer can precipitate above its lower critical solubility temperature (LCST) and separate from the nonspecific by gentle centrifugation, which may simply the downstream processing. However, this method may be limited due to low grafting efficiency of the macromolecules to the glycan tag of proteins.