An Electrical Particle Velocity Profiler Using Particle Transit Time Across Uneven Inter-Gap Electrodes

비등간격 전극열에서의 입자 통과시간을 이용한 전기적 입자속도분포 검출기

  • 김태윤 (KAIST 바이오및뇌공학과, 디지털나노구동 연구단) ;
  • 이동우 (KAIST 바이오및뇌공학과, 디지털나노구동 연구단) ;
  • 조영호 (KAIST 바이오및뇌공학과 및 기계공학과, 디지털나노구동연구단)
  • Published : 2008.04.01


We present an electrical particle velocity profiler using particle transit time across uneven inter-gap electrodes. We measure both the particle position and velocity from the voltage signals generated by the particles passing across sensing electrodes, thus obtaining the velocity profile of the particles in a microfluidic channel. In the experimental study, we use polystyrene microparticles to characterize the performance of the electrical particle velocity profiler. The particle velocity profile is measured with the uncertainty of 5.44%, which is equivalent to the uncertainty of 5% in the previous optical method. We also experimentally demonstrate the capability of the present method for in-channel clogging detection. Compared to the previous optical methods, the present electrical particle velocity profiler offers the simpler structure, the cheaper cost, and the higher integrability to micro-biofluidic systems.


Particle Velocity Profiler;Particle Transit Time;Particle Image Velocimetry;In-Channel Clogging Detection


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