Preparation and Properties of a Low Fouling Magnetic Nanoparticle and Its Application to the HPV Genotypes Assay in Whole Serum

Gold magnetic particles as a new carrier of disease diagnosis probes have attracted wide attention but encountered a bottleneck. That is, the interfacial properties of gold magnetic particles are susceptible to the influence of nonspecific biological molecules in actual diagnostic samples. Here, a novel nanoparticle made by the covalent attachment of polyethyleneimine and hyperbranched polyether polyol onto the gold shell surface of a magnetic bead demonstrated not only low fouling properties but also excellent stability in a variety of external environments, especially in complex biological systems. Most importantly, in its application as the probe for sensitive and selective fluorescence detection of high-risk human papillomavirus (HPV) genotypes 18, 16 in buffer, even in 100% serum, a good linear correlation with the concentration of HPV18/16 target DNA ranging from 5 nM to 1 mu M was shown with the low detection limits. To our knowledge, this is one of the few successful examples of direct application of magnetic beads to the detection of disease markers in whole serum, suggesting that this material has good commercial potential and value.