Biomedical Microdevices

, 9:833 | Cite as

Multiple-channel emulsion chips utilizing pneumatic choppers for biotechnology applications

  • Yen-Heng Lin
  • Cheng-Tso Chen
  • Lynn L. H. Huang
  • Gwo-Bin Lee


The formation of micro-scale monodispersed emulsions is crucial for a variety of applications such as cosmetics, food industry and biotechnology. In this study, a new microfluidic chip with a multiple-channel layout for high-throughput emulsions is reported. This chip generated fine-tuned and uniform microdroplets in liquids with a higher throughput for emulsification applications. It employed a combination of multiple hydrodynamic flow focusing and liquid-cutting devices called “active pneumatic choppers.” Experimental data indicated that oil-in-water microdroplets with diameters ranging from 6 to 120 μm can be successfully generated with a coefficient of variation less than 3.75%. The size of the droplets can be actively fine-tuned by using two approaches by adjusting relative sheath/sample flow velocity ratios and chopping frequency. Finally, two commonly used biocompatible materials, including collagen and calcium-alginate (Ca-alginate), were used to form microspheres by utilizing the liquid-cutting technique. The developed microfluidic chip is promising in various applications including biotechnology, nano-medicine and cosmetics.


Emulsification Choppers Hydrodynamic flow focusing Microdroplet Microfluidics MEMS Collagen Alginate 





charge-coupled device

DI water

deionized water


deoxyribonucleic acid


electromagnetic valve


operating frequency of EMV


hydrophilic lipophilic balance








polymerase chain reaction


scanning electron microscope


sample flow velocity


sheath flow velocity







The authors would like to thank partial financial support from the National Science Council in Taiwan. Access to major fabrication equipment at the Center for Micro/Nano Technology Research, National Cheng Kung University is also greatly appreciated.


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Yen-Heng Lin
    • 1
  • Cheng-Tso Chen
    • 1
  • Lynn L. H. Huang
    • 2
  • Gwo-Bin Lee
    • 1
  1. 1.Department of Engineering ScienceNational Cheng Kung UniversityTainanRepublic of China
  2. 2.Institute of BiotechnologyNational Cheng Kung UniversityTainanRepublic of China

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