State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Nanjing 210096, PR China.
J Biomed Nanotechnol. 2012 Dec;8(6):1000-5. doi: 10.1166/jbn.2012.1454.
In this article, we present an easy route to prepare monodisperse core-shell Fe3O4@SiO2 microspheres with uniform size and shape. Their structures and properties were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR), and vibrating sample magnetometer (VSM), respectively. The results showed that spherical Fe3O4 microspheres with well dispersion have a rough surface and an average diameter (about 500 nm). After the modification with silica, the particles have a well-defined core-shell structure and a much smoother surface and larger particle diameter (about 600 nm). Furthermore, VSM measurements indicated that the as-prepared Fe3O4 and Fe3O4@SiO2 microspheres were superparamagnetic at room temperature and the saturation magnetization (M(s)) were 58.110 emu/g and 33.479 emu/g, respectively. And then, the prepared monodisperse core-shell Fe3O4@SiO2 microspheres were subsequently applied to separate nucleic acids from the bacteria (E. coli BL21) and verified the great application prospects for bioseparation technology of the biomoleculars.
本文提出了一种简便的方法来制备具有均匀尺寸和形状的单分散核壳 Fe3O4@SiO2 微球。通过透射电子显微镜（TEM）、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FT-IR）和振动样品磁强计（VSM）分别对其结构和性能进行了研究。结果表明，具有良好分散性的球形 Fe3O4 微球具有粗糙的表面和平均直径（约 500nm）。经过二氧化硅修饰后，颗粒具有明确的核壳结构，表面更加光滑，粒径更大（约 600nm）。此外，VSM 测量表明，所制备的 Fe3O4 和 Fe3O4@SiO2 微球在室温下具有超顺磁性，饱和磁化强度（M(s)）分别为 58.110 emu/g 和 33.479 emu/g。然后，将制备的单分散核壳 Fe3O4@SiO2 微球用于从细菌（E. coli BL21）中分离核酸，并验证了其在生物分子生物分离技术中的广阔应用前景。
