Differences in magnetically induced motion of diamagnetic, paramagnetic, and superparamagnetic microparticles detected by cell tracking velocimetry
Differences in magnetically induced motion of diamagnetic, paramagnetic, and superparamagnetic microparticles detected by cell tracking velocimetry
复制标题
DOI：
10.1039/b802113a
复制
发表时间：
2008-01-01
期刊：
影响因子：
4.2
通讯作者：
Chalmers, Jeffrey J.
中科院分区：
文献类型：
--
作者：
Jin, Xiaoxia;Zhao, Yang;Chalmers, Jeffrey J.
生物医学应用中的磁分离是基于粘性介质中微粒物质的微分磁泳迁移率（MM）。通常，通过用超顺磁性氧化铁纳米颗粒（SPION）选择性标记靶细胞来获得MM的差异。我们已经测量了MM的单分散性，聚苯乙烯微球（PSM），有和没有附加SPION作为模型的纳米粒子磁化诱导的细胞运动，使用可变H场和细胞跟踪测速仪（CTV）。作为顺磁性微粒运动的模型，在顺磁性钆溶液中的相同PSM上以及在原核生物球形芽孢杆菌（显示含有顺磁性锰）的孢子上进行MM测量。的CTV分析是敏感的微粒磁化的类型，产生MM的值独立于所施加的H场的顺磁性物质，和MM值随着场的增加超顺磁性物质，从理论上预测。SPION标记的PSM表现出高于Hy的饱和磁化强度，相当于64 000 A m（-1）（或0.08特斯拉）。基于这些数据，计算了SPION的平均饱和磁化强度，并显示出不同商业来源之间的差异。结果表明CTV分析对微粒的不同磁化机制的灵敏度。
Magnetic separation in biomedical applications is based on differential magnetophoretic mobility (MM) of microparticulate matter in viscous media. Typically, the difference in MM is obtained by selectively labeling the target cells with superparamagnetic iron oxide nanoparticles (SPIONs). We have measured the MM of monodisperse, polystyrene microspheres (PSMs), with and without attached SPIONs as a model of cell motion induced by nanoparticle magnetization, using variable H field and cell tracking velocimetry (CTV). As a model of paramagnetic microparticle motion, the MM measurements were performed on the same PSMs in paramagnetic gadolinium solutions, and on spores of a prokaryotic organism, Bacillus globigii (shown to contain paramagnetic manganese). The CTV analysis was sensitive to the type of the microparticle magnetization, producing a value of MM independent of the applied H field for the paramagnetic species, and a decreasing MM value with an increasing field for superparamagnetic species, as predicted from theory. The SPION-labeled PSMs exhibited a saturation magnetization above Hy congruent to 64 000 A m(-1) (or 0.08 tesla). Based on those data, the average saturation magnetizations of the SPIONs was calculated and shown to vary between different commercial sources. The results demonstrate sensitivity of the CTV analysis to different magnetization mechanisms of the microparticles.