Preparation And Application Of Magnetic Luminescent Multi-functional PGMA Microspheres

In this paper, dispersion polymerization was used to prepare micron-sized uniform poly(glycidylmethacrylate) (PGMA) microspheres, 2,2'-azo-bis-isobutyro- nitrile (AIBN) as initiator, polyvinylpyrrolidone(PVP) as stabilizer, alcohol and water as polymerization media. The effects of different monomer concentration, PVP concentration, reaction temperature on the dispersion polymerization of GMA have been investigated. We optimized the reaction conditions and 1.7-3.1μm,uniform PGMA microspheres were successfully prepared. Ethylene diamine was used to modify PGMA microspheres. FTIR showed that ?NH2 was successfully introduced into PGMA microspheres and the ?NH2 concentration was about 3mmol/g by two abrupt change titration method.Amino-PGMA as carrier, two methods were used to prepare multifunctional microspheres with magnetic and luminescent, one was situ precipitation method, the other was swell-infuse method. SEM showed that the morphology of multifunctional microspheres were regular and monodisperse; XRD and VSM showed that the multifunctional microsphreres were superparamagnetic. The saturation magnetization value of magnetic microspheres was 4.6emu/g at 300 K. Strong pink fluorescence emission was observed by digital fluorescence microscopy. Magnetic separation under UV lamp showed that the multifunctional microspheres with both magnetic and luminescent properties.Multifunctional microspheres by swell-infuse method were applied in biomedical detection, showed that the microspheres were easily connected with antibody. Corresponding antigen could be identified by antibody-microspheres. Different antigens could be easily distinguished under digital fluorescence microscopy. Also the multifunctional microspheres could be detected by flow cytometry, indicating the microspheres are promising to be used in immune assays.