Hwang Hyundoo, Kim Jae-Jun, Park Je-Kyun
Department of Bio and Brain Engineering, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, Republic of Korea.
J Phys Chem B. 2008 Aug 14;112(32):9903-8. doi: 10.1021/jp803596r. Epub 2008 Jul 23.
This paper reports experimental and theoretical investigation of electrostatic attraction and repulsion of microparticles in an optoelectronic tweezers (OET). When we manipulate dielectric particles suspended in a fluid using OET, the electrostatic interactions of the polarized particles occur, limiting the effective manipulation of microparticles using a light-induced dielectrophoresis. In this study, we first demonstrate the electrostatic particle-particle interactions in the OET device using a liquid crystal display. At the same time, the experimental investigation of the dipole interactions between two spherical particles has been performed using the OET device. On the basis of the point-dipole model, simulation studies on the dipole forces acting on the particles and their trajectories by the forces are also performed. The experimental results show good agreement with the previously reported numerical studies as well as the results of our simulation studies.
本文报道了对光电镊子（OET）中微粒静电吸引和排斥的实验与理论研究。当我们使用光电镊子操纵悬浮在流体中的介电粒子时，极化粒子会发生静电相互作用，这限制了利用光诱导介电泳对微粒进行有效操纵。在本研究中，我们首先利用液晶显示器展示了光电镊子装置中的静电粒子间相互作用。同时，利用该光电镊子装置对两个球形粒子之间的偶极相互作用进行了实验研究。基于点偶极模型，还对作用在粒子上的偶极力及其受力轨迹进行了模拟研究。实验结果与先前报道的数值研究以及我们的模拟研究结果吻合良好。
