Kang Yuejun, Li Dongqing, Kalams Spyros A, Eid Josiane E
Department of Mechanical Engineering, Vanderbilt University, 2301 Vanderbilt Place, Nashville, TN 37235, USA.
Biomed Microdevices. 2008 Apr;10(2):243-9. doi: 10.1007/s10544-007-9130-y.
DC-Dielectrophoresis (DC-DEP), the induced motion of the dielectric particles in a spatially non-uniform DC electric field, is applied to separate biological cells by size. The locally non-uniform electric field is generated by an insulating hurdle fabricated within a PDMS microchannel. The cells experience a negative DEP (accordingly a repulsive) force at the corners of the hurdle where the gradient of local electric-field strength is the strongest. The DC-DEP force acting on the cells is proportional to the cells' size. Thus the moving cells deviate from the streamlines and the degree of deviation is dependent on the cell size. In this paper, we demonstrated by using this method that, combined with the electroosmotic flow, mixed biological cells of a few to tens of micrometers difference in diameter can be continuously separated into different collecting wells. For separating target cells of a specific size, all that is required is to adjust the voltage outputs of the electrodes.
直流介电泳（DC - DEP），即电介质颗粒在空间非均匀直流电场中的感应运动，被用于按大小分离生物细胞。局部非均匀电场由在聚二甲基硅氧烷（PDMS）微通道内制造的绝缘障碍物产生。细胞在障碍物的角落处会受到负介电泳力（相应地是排斥力），此处局部电场强度的梯度最强。作用在细胞上的直流介电泳力与细胞大小成正比。因此，移动的细胞会偏离流线，且偏离程度取决于细胞大小。在本文中，我们通过使用这种方法证明，结合电渗流，可以将直径相差几微米到几十微米的混合生物细胞连续分离到不同的收集孔中。为了分离特定大小的目标细胞，所需要做的就是调整电极的电压输出。
