Microfluidic devices in superconducting magnets: on-chip free-flow diamagnetophoresis of polymer particles and bubbles
Microfluidic devices in superconducting magnets: on-chip free-flow diamagnetophoresis of polymer particles and bubbles
复制标题
DOI：
10.1007/s10404-012-0979-6
复制
发表时间：
2012-05
影响因子：
2.8
通讯作者：
M. Vojtíšek;M. Tarn;N. Hirota;N. Pamme
中科院分区：
文献类型：
--
作者：
M. Vojtíšek;M. Tarn;N. Hirota;N. Pamme
超导磁体可以研究材料和物体上的强磁场，例如材料合成、自组装或悬浮实验。所采用的设置通常缺乏对磁体孔内感兴趣物体的精确空间控制。微流体技术能够精确操纵流体环境，我们研究了将微流体装置集成到超导磁体中，以便能够对强磁场中的物体进行受控研究。通过抗磁斥力操纵大小与生物细胞相似的聚合物微粒。这些颗粒悬浮在氯化锰 (II) 水性顺磁介质中，并被泵入微流体芯片中，在高磁场的作用下，它们以连续流动的方式被排斥。研究了偏转程度与 (1) 颗粒尺寸、(2) 顺磁性盐浓度和 (3) 磁场强度增加的函数关系。优化这些参数可以通过片上自由流动抗磁泳实现两个粒子群的空间分离。最后，显示了关于气泡排斥的初步发现。
Superconducting magnets enable the study of high magnetic fields on materials and objects, for example in material synthesis, self-assembly or levitation experiments. The setups employed often lack in precise spatial control of the object of interest within the bore of the magnet. Microfluidic technology enables accurate manipulation of fluidic surroundings and we have investigated the integration of microfluidic devices into superconducting magnets to enable controlled studies of objects in high magnetic fields. Polymeric microparticles similar in size to biological cells were manipulated via diamagnetic repulsion. The particles were suspended in an aqueous paramagnetic medium of manganese (II) chloride and pumped into a microfluidic chip, where they were repelled in continuous flow by the high magnetic field. The extent of deflection was studied as a function of increasing (1) particle size, (2) paramagnetic salt concentration, and (3) magnetic field strength. Optimizing these parameters allowed for the spatial separation of two particle populations via on-chip free-flow diamagnetophoresis. Finally, preliminary findings on the repulsion of air bubbles are shown.