用于高效磁转染的鱼精蛋白修饰的铁氧磁性纳米粒研究

 功能化铁氧磁性纳米粒在生物医学中应用广泛，可用于肿瘤磁感应热疗、磁共振成像（Magnetic Resonance Imaging，MRI）、药物输送及磁转染等方面。为了探讨鱼精蛋白功能化修饰的铁氧磁性纳米粒的制备及其作为基因载体在体外磁转染中的可行性，采用共沉淀法制备Fe3O4磁性纳米粒，经表面氨基化修饰后在其表面偶联鱼精蛋白。利用透射电镜、傅里叶红外光谱仪、zeta电位与粒度分析仪等，对磁性纳米粒进行形态、粒径及zeta电位分析等表征检测。共聚焦显微镜观察磁转染方法转染报告基因绿色荧光蛋白质粒pEGFP-N1进入HepG2细胞的表达，以真核转染试剂vigofect为对照。结果显示，实验中制备的磁性纳米粒粒径10nm左右，在交变磁场下具有良好的升温性能。鱼精蛋白功能化修饰磁性纳米粒后，其zeta电位进一步增大，更利于与DNA有效结合，在HepG2细胞系，其转染pEGFP-N1质粒的效率高于vigofect。研究表明，鱼精蛋白功能化修饰的铁氧磁性纳米粒可作为磁转染的有效载体，由于其同时具备在交变磁场下升温的性能，在基因治疗联合热疗的研究领域具有一定的应用价值。

Protamine-Modified Iron Oxide Magnetic Nanoparticles are Efficient Gene Vectors for Magnetofection

Functionalized magnetic iron oxide nanoparticles (MNPs) can play crucial roles in medical applications, including cancer magnetic fluid hyperthermia, magnetic resonance imaging, anticancer drug delivery, and magnetofection. Here, the use of modified MNPs coated with protamine peptides containing nuclear localization signal sequences as gene carriers (PRO-MNPs) for magnetofection of HepG2 cells was tested. Fe3O4 nanoparticles were synthesized by chemical co-precipitation, modified by 3-aminopropyltriethoxysilane, and were covalently attached to protamine. The size, zeta potential, and coating characteristics of MNPs were analyzed by transmission electron microscopy, Zetaplus zeta potential measurement, and Fourier transform infrared imaging, respectively. The magnetofection efficiency of PRO-MNPs was observed by a laser scanning confocal microscope using pEGFP-N1 as the reporter gene. The mean size of the magnetic nanoparticles was about 10nm. The expression level of green fluorescence protein in HepG2 cells transfected with PRO-MNPs was significantly higher than that of cells transfected using vigofectin reagent. The results indicate that PRO-MNPs offer a novel non-viral gene transfection vector, particularly for cancer gene therapy when combined with magnetic-induced hyperthermia.