Abstract: APTES-bounded MNP were prepared by chemical coprecipitation, followed by coating with (γ-aminopropyl)triethoxysilane. Norvancomycin hydrochloride(Van) was then immobilized onto the amino-functionalized nanopartiles. Powder X-ray diffraction(XRD) results show the inverse spinel structure of MNP. The physics property measurement system(PPMS) indicates that the MNP are superparamagnetic. The presence of Van and APTES on the surface of MNP is confirmed by FTIR. By a separation assay of S. aureus and E. coli BL21, it is proved that MNP-APTES-Van can selectively capture S. aureus within 10 min, which can be isolated readily by applying an external magnetic field.

Key words: Magnetite nanoparticles, Vancomycin, Bioconjugate, Bacterial separation