After repeating thermoprecipitation and centrifugation steps, the results of SDS-PAGE was shown in Fig. 4, there was a non-specific band at 37 kDa in Lane 3, but no other non-specific band. It is mean that the polymer in E. coli lysate can be obtained by simple thermal centrifugation, and the separation effect was remarkable. These results verified that the HRP-pNIPPAm based on oximation reaction and ATRP technology has good separation and enrichment ability and strong specificity in complex environment, which provides a feasible scheme for glycoprotein separation and enrichment.