24 4 4 2012 4 Vol. 24 No. 4 Chemical Research and Application Apr. 2012 1004-1656 2012 04-0503-06 * 361005 SEM 7. 77 μm PDI 1. 03 Fe 3 O 4 FT-IR TG Fe 3 O 4 Fe 3 O 4 O632. 13 A Preparation of polystyrene magnetic microspheres for liquid chips by dispersion polymerization NIU Ning-ning ZHOU Lei-ji * LIU Guo-an JIANG Shu-juan Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China Abstract We present an approach of synthesizing magnetic polystyrene complex microspheres by a facile dispersion polymerization. Monodisperse magnetic polystyrene microspheres appropriate to construct liquid chip carriers were prepared via dispersion polymerization by dispersing pre-treated acrylic acid-based magnetic fluid in styrene. The effects of synthetic conditions such as pretreatment time of acrylic acid-based magnetic fluid feeding sequence and amount of styrene monomer on particles conformation and their size distribution have been investigated and parameters were further optimized accordingly. SEM results indicate that the magnetic microspheres have an average diameter of 7. 77 μm with excellent monodispersity PDI 1. 03 and smooth and compact surfaces. Magnetization curve of Fe 3 O 4 nanoparticles was obtained using superconducting quantum magnetometer. Chemical structures and content of magnetic Fe 3 O 4 of the microspheres were characterized and analyzed using FT-IR and TGA methods. Key words Fe 3 O 4 polystyrene magnetic microsphere dispersion polymerization 2011-08-12 2011-10-08 20775065 20835005 20070384023 J1030415 1971- E-mail ljzhou@ xmu. edu. cn
504 24 1 2 3 7 8 9 10 12 13 4-6 AA MRI 11 P St-AA 14 FT-IR TGA SEM TEM 1 5 μm 1. 1 Fe acac 3 98% aladdin AR 80-90% AR St CR AA CR PVP K 30 AIBN AR 15 St N- N-isopropylacrylamide NIPAM PSNN 1. 2. 1 Fe 3 O 4 Fe acac 3 1. 2 1 mmol Fe 5-35 μm Liu et acac 3 1. 5 ml 1. 5 ml 9 ml al 16 17 St /NH 2 -PEO-AA St /PEO-VB P St-MPEO 5-80μm 5-100 Fe 3 O 4 μm Zeng 18 1. 2. 2 PEG Fe 3 O 4 St AA PEG 250 ml 1. 0 g PVP 2 μm Zhang et 23. 1 ml V EtOH /V H2 O = 10 1 0. 1 g al 19 72% P Fe 3 O 4 1 ml AA 25 St GMA 1 h 0. 1 g AIBN 0. 5-1 μm 10 g St PVP 10 min 70 8 h N 2 3 1. 3 X X'pert PRO Fe 3 O 4 Fe 3 O 4
4 505 JEM-2100 Fe 3 O 4 Hitachi S-4800 200 120 min AA PDI MPMS-XL-7 1 Quantum Design Fe 3 O 4 Table 1 Effect of pretreatment time on size and size Nicolet distribution of magnetic microspheres Avatar 330 Min D n PDI 30 12. 89 1. 22 SDT Q600 TA 60 10. 55 1. 04 Fe 3 O 4 90 2. 47 1. 20 120 2 2. 1. 2 2. 1 2. 1. 1 AA Fe 3 O 4 AA AA Fe 3 O 4 AIBN AA AIBN AIBN Fe 3 O 4 PVP 70 PVP 0. 5 g 1. 4 g 25 30 60 90 120 min PDI 1 30 min 60 2. 1. 3 min 1 h 20 90 min 10 g 8 g 6 g 2 6
506 24 g St 2920 2850 cm -1 -CH 2 - C-H 1705 cm -1 C = O 10 g 8 g 8 g 7. 77 μm PDI 1. 03 Table 2 2 Effect of monomer on size and size distribution of magnetic microspheres g D n 10 10. 55 1. 04 PDI 8 7. 77 1. 03 6 1 a. Fe 3 O 4 b. 2. 2 XRD Fig. 2 FT-IR spectra for analysis of chemical structures. 1 Fe 3 O 4 X a. Fe 3 O 4 nanoparticles b. magnetic polystyrene microspheres 2θ 30. 26 35. 55 43. 21 53. 53 57. 17 62. 73 74. 05 2. 4 Fe 3 O 4 Fe 3 O 4 00-001-1111 3 P St-AA 2θ 340 35. 55 5. 7 nm 340 ~ 500 500 Fe 2 O 3 Fe 3 O 4 Fe 2 O 3 Fe 2 O 3 Fe 3 O 4 4. 3% 1 Fig. 1 Fe 3 O 4 XRD X-ray diffraction patterns of the iron oxide nanoparticles 2. 3 2 P St-AA 2a 580 cm -1 Fe 3 O 4 Fe-O 3 2b 580 cm -1 Fig. 3 Fe-O 3082 ~ 3024 cm -1 C-H 1601 ~ 1450 cm -1 756 698 cm -1 C-H 10 /min TGA analysis of magnetic polystyrene microspheres. The curve was obtained at a heating rate of 10 /min under a oxygen atmosphere
4 507 2. 5 5b 5a Fe 3 O 4 TEM 4 10 min Fe 3 O 4 7. 77 μm PDI 1. 03 Fe 3 O 4 5c 5. 4 nm 21 Fe 3 O 4 35 nm P St-AA 20s 5 SEM Fig. 4 4 Fe 3 O 4 a. TEM b. c. Characterization of Fe 3 O 4 nanopariticles. a. TEM photograph b. size distribution c. magnetization curve 3 5 a b. SEM c. Fig. 5 Conformation and magnetic response characteristic of magnetic polystyrene microspheres. a and b. SEM photograph c. magnetic response characteristic P St-AA 5. 4 nm Fe 3 O 4 Fe 3 O 4 AA
508 24 1 Obata K Tajima H Yohda M et al. Recent developments in laboratory automation using magnetic particles for genome analysis J. Pharmacogenomics 2002 3 5 697-708. 2 Goldner H. MATERIALS PRODUCTS J. R&D Mag. 1994 4 36 32-33. 3 Safarik I Safarikova M. Magnetic techniques for the isolation and purification of proteins and peptides J. Biomagn Res. Technol. 2004 2 1 7. 4 Pamme N. Magnetism and microfluidics J. Lab Chip 2006 6 1 24-38. 5 Prestvik W S Berge A Mork P C et al. Preparation and application of monosized magnetic particles in selective cell separation Scientific and clinical applications of magnetic carriers 1997 C. 6 Safar I K I Safar I Kova M. Use of magnetic techniques for the isolation of cells J. J. Chromatogr. B 1999 722 33-53. 7 Rittich B Spanova A Salek P et al. Separation of PCRready DNA from dairy products using magnetic hydrophilic microspheres and poly ethylene glycol -NaCl water solutions J. J. Magn. Magn. Mater. 2009 321 10 1667-1670. 8 Weizmann Y Patolsky F Katz E et al. Amplified DNA Sensing and Immunosensing by the Rotation of Functional Magnetic Particles J. J. Am. Chem. Soc. 2003 125 12 3452-3454. 9 Liu Z Zhang L Yang H et al. Magnetic microbead-based enzyme-linked immunoassay for detection of Schistosoma japonicum antibody in human serum J. Anal. Biochem. 2010 404 2 127-134. 10 Gupta A K Gupta M. Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications J. Biomaterials 2005 26 18 3995-4021. 11 Yezhelyev M V Gao X Xing Y et al. Emerging use of nanoparticles in diagnosis and treatment of breast cancer J. Lancet Oncol. 2006 7 8 657-667. 12 Rorrer G L Hsien T Y Way J D. Synthesis of porousmagnetic chitosan beads for removal of cadmium ions from wastewater J. Ind. Eng. Chem. Res. 1993 32 9 2170-2178. 13 Guo S S Zuo C C Huang W H et al. Response of superparamagnetic beads in microfluidic devices with integrated magnetic micro-columns J. Microelectron. Eng. 2006 83 4-9 1655-1659. 14 Zhou L Wang K Tan W et al. Quantitative Intracellular Molecular Profiling Using a One-Dimensional Flow System J. Anal. Chem. 2006 78 17 6246-6251. 15. J. 1999 6 674-679. 16 Liu X Y Ding X B Zheng Z H et al. Synthesis of novel magnetic polymer microspheres with amphiphilic structure J. J. Appl. Polym. Sci. 2003 90 7 1879-1884. 17 Liu X Y Ding X B Zheng Z H et al. Synthesis of amphiphilic magnetic microspheres by dispersion copolymerization of styrene and poly ethylene oxide macromonomer J. Polym. Int. 2003 52 2 235-240. 18 Zeng H M Lai Q Y Liu X Q et al. Factors influencing magnetic polymer microspheres prepared by dispersion polymerization J. J. Appl. Polym. Sci. 2007 106 5 3474-3480. 19 Zhang J Yu D M Chen W et al. Preparation of poly styrene-glucidylmethacrylate /Fe3O4 composite microspheres with high magnetite contents J. J. Magn. Magn. Mater. 2009 321 6 572-577. 20. J. 2009 48 6 854-857. 21 Dunlop D J. Magnetite Behavior near the Single-Domain Threshold J. Science 1972 176 4030 41-43.