趋磁螺菌纳米磁小体的特征及标准化检测体系

Characterization and standardized detection system of magnetosomes in Magnetospirillum gryphiswaldense

目的:纯化趋磁螺菌细胞内合成的纳米级四氧化三铁颗粒(磁小体),并对其进行表征,建立标准化检测体系。方法:采用磁性分离系统获得磁小体,分别用透射电镜(TEM)、X射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)、动态光散射(DLS)、zeta电位测定、室温磁滞回线测量等方法进行表征。结果:TEM分析显示,磁小体平均粒径约为43 nm,XRD线宽化法计算其晶粒大小约为35 nm;TEM和FTI-R分析显示,纯化的磁小体表面的质膜完整,—NH2存在,可作为连接其他化合物的位点;zeta电位分析表明,在水溶液中磁小体表面的zeta电位为-32.3 mV,体系比较稳定。结论:纯化磁小体颗粒均匀,有膜包被,可作为核酸、蛋白、药物的载体而应用于不同领域。

Objective： To purify magnetosomes,characterize them and build a standardized detection system.Methods： Magnetosomes were purified from cells of Magnetospirillum gryphiswaldense MSR-1 based on their magnetism,and were characterized by TEM,XRD,FT-TR,DSL,zeta potential and normalized hysteresis loop.Results：（1） TEM,XRD studies showed that the magnetosomes had a particle diameter of 43 nm and a crystal size of 35 nm;（2） TEM observed and FT-IR analyzed results indicated that the magnetosome membrane existed,and there were-NH2 and other groups on the membrane;（3） Zeta potential analysis revealed that the surface charge of magnetosomes was-32.3 mV in ultrapure water.Conclusion： Purified magnetosomes have a uniform size and the membrane exists.So they can be applied to different areas as carriers of nucleic acids,proteins and drugs.