Yu Shang Lai

Publications (2)9.7 Total impact

• Article: Trapping of bioparticles via microvortices in a microfluidic device for bioassay applications.

  Cheng Ming Lin, Yu Shang Lai, Hsin Ping Liu, Chang Yu Chen, Andrew M Wo
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  ABSTRACT: This paper presents hydrodynamic trapping of bioparticles in a microfluidic device. An in-plane oscillatory microplate, driven via Lorentz law, generates two counter-rotating microvortices, trapping the bioparticles within the confines of the microvortices. The force required to trap bioparticles is quantified by tuning the background flow and the microplate's excitation voltage. Trapping and releasing of 10-microm polystyrene beads, human embryonic kidney (HEK) cells, red blood cells (RBCs), and IgG antibodies were demonstrated. Results show the microvortices rotates at 0-6 Hz corresponding to 2-9 Vpp (peak-to-peak) excitation. At a particular rate of rotation (2-7 Vpp tested), a bioparticle is trapped until the background flow exceeds a limit. This flow limit increases with the rate of rotation, which defines the trap/release force boundary over the range of operation. This boundary is 12 +/- 2.0 pN for cell-size bioparticles and 160 +/- 50 fN for antibodies. Trapping of RBCs demonstrated microvortices' ability for nonspherical cells. Cell viability was studied via HEK cells that were trapped for 30 min and shown to be viable. This hydrodynamically controlled approach to trap a wide range of bioparticles should be useful as a microfluidic device for cellular and subcellular bioassay applications.
  Analytical Chemistry 01/2009; 80(23):8937-45. · 5.86 Impact Factor
• Source

  Available from: Andrew M Wo

  Article: Microvortices and recirculating flow generated by an oscillatory microplate for microfluidic applications

  Cheng Ming Lin, Yu Shang Lai, Hsin Ping Liu, Andrew M. Wo
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  ABSTRACT: Circulatory flow structures can be useful in a microfluidic device but often are difficult to generate mechanically in microscale. This paper presents generation of such flow via an in-plane resonating microplate (100×100×1.2 μm3) actuated by Lorentz law. Results show either one of two nonlinear time-mean flow structures is feasible for the finite plate: (1) two-dimensional (2D) small-scale, counter-rotating microvortices or (2) three-dimensional, large-scale, recirculating flow. Sharpness of microplate’s edge is found to be the decisive factor for 2D microvortices to form. Both flow structures are robust and controllable. Potential applications include trapping and mixing of bioparticles in microfluidic devices.
  Applied Physics Letters 09/2008; 93(13):133503-133503-3. · 3.84 Impact Factor