Department of Mechanical Engineering, University College London, London, UK.
Mater Sci Eng C Mater Biol Appl. 2013 Aug 1;33(6):3129-37. doi: 10.1016/j.msec.2013.03.001. Epub 2013 Mar 14.
Magnetic microspheres were prepared using a single step coaxial electrohydrodynamic atomization technique at ambient temperature and pressure, with poly(lactic-co-glycolic acid) as the coating and iron oxide (Fe3O4) nanoparticles dispersed in polyethylene glycol as the encapsulated material. The morphology and particle size distributions of the prepared magnetic microspheres were investigated by scanning electron microscopy. The particles were spherical with mean diameters ranging from ~2 μm to 18 μm, depending on the combination of processing parameters (flow rate and applied voltage). Analysis by infrared spectroscopy and focused ion-beam sectioning confirmed incorporation of iron oxide nanoparticles into the microspheres and the prepared samples were shown to be responsive to an applied magnetic field. This study demonstrates a convenient method for the preparation of nanoparticle loaded microspheres, which could be used potentially as transverse relaxation contrast agents in magnetic resonance imaging, as well as for magnetically guided drug delivery.
磁性微球采用单步同轴电动力学雾化技术在环境温度和压力下制备，以聚（乳酸-共-乙醇酸）为涂层，以分散在聚乙二醇中的氧化铁（Fe3O4）纳米颗粒为包裹材料。通过扫描电子显微镜研究了制备的磁性微球的形态和粒径分布。颗粒呈球形，平均直径范围为~2μm 至 18μm，取决于加工参数（流速和施加电压）的组合。通过红外光谱分析和聚焦离子束切片证实了氧化铁纳米颗粒已掺入微球中，并且所制备的样品对施加的磁场有响应。这项研究展示了一种制备载纳米颗粒微球的简便方法，该方法可潜在用作磁共振成像中的横向弛豫对比剂，以及用于磁性导向药物输送。
