Takeda Shin-ichi, Terazono Bungo, Mishima Fumihito, Nakagami Hironori, Nishijima Shigehiro, Kaneda Yasufumi
Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
J Nanosci Nanotechnol. 2006 Sep-Oct;6(9-10):3269-76. doi: 10.1166/jnn.2006.483.
In the recent progress of gene and cell therapy, novel drug delivery system (DDS) has been required for efficient delivery of small molecules/drugs and also the safety for clinical usage. We have already developed the unique transfection technique by preparing magnetic vector and using permanent magnet. This technique can improve the transfection efficiency. In this study, we directly associated plasmid DNA with magnetic nanoparticles, which can potentially enhance their transfection efficiency by magnetic force. Magnetic nanoparticle, such as magnetite, its average size of 18.7 nm, can be navigated by magnetic force and is basically consisted with oxidized Fe that is commonly used as the supplement drug for anemia. The magnetite particles coated with protamine sulfate, which gives a cationic surface charge onto the magnetite particle, significantly enhanced the transfection efficiency in vitro cell culture system. The magnetite particles coated with protamine sulfate also easily associated with cell surface, leading to high magnetic seeding percentage. From these results, it was found that the size and surface chemistry of magnetic particles would be tailored to meet specific demands on physical and biological characteristics accordingly. Overall, magnetic nanoparticles with different surface modification enhance the association with plasmid DNA and cell surface as well as HVJ-E, which potentially help to improve the drug delivery system.
在基因和细胞治疗的最新进展中，高效递送小分子/药物以及临床使用安全性方面需要新型药物递送系统（DDS）。我们已经通过制备磁性载体并使用永久磁铁开发了独特的转染技术。该技术可以提高转染效率。在本研究中，我们将质粒DNA直接与磁性纳米颗粒结合，这有可能通过磁力提高其转染效率。磁性纳米颗粒，如磁铁矿，其平均粒径为18.7nm，可通过磁力导航，基本上由常用作贫血补充药物的氧化铁组成。硫酸鱼精蛋白包被的磁铁矿颗粒在磁铁矿颗粒表面赋予阳离子表面电荷，显著提高了体外细胞培养系统中的转染效率。硫酸鱼精蛋白包被的磁铁矿颗粒也很容易与细胞表面结合，导致高磁接种率。从这些结果发现，磁性颗粒的大小和表面化学性质将相应地进行调整以满足对物理和生物学特性的特定要求。总体而言，具有不同表面修饰的磁性纳米颗粒增强了与质粒DNA和细胞表面以及HVJ-E的结合，这可能有助于改善药物递送系统。
