Microfluidics and Nanofluidics

, Volume 8, Issue 2, pp 255–262 | Cite as

Microchannel emulsification for mass production of uniform fine droplets: integration of microchannel arrays on a chip

  • Isao Kobayashi
  • Yoshihiro Wada
  • Kunihiko Uemura
  • Mitsutoshi Nakajima
Short Communication


We present a novel microchannel emulsification (MCE) system for mass-producing uniform fine droplets. A 60 × 60-mm MCE chip made of single-crystal silicon has 14 microchannel (MC) arrays and 1.2 × 104 MCs, and each MC array consists of many parallel MCs and a terrace. A holder with two inlet through-holes and one outlet through-hole was also developed for simply infusing each liquid and collecting emulsion products. The MCE chip was sealed well by physically attaching it to a flat glass plate in the holder during emulsification. Uniform fine droplets of soybean oil with an average diameter of 10 μm were reliably generated from all the MC arrays. The size of the resultant fine droplets was almost independent of the dispersed-phase flow rate below a critical value. The continuous-phase flow rate was unimportant for both the droplet generation and the droplet size. The MCE chip enabled mass-producing uniform fine droplets at 1.5 ml h−1 and 1.9 × 109 h−1, which could be further increased using a dispersed phase of low viscosity.


Microchannel emulsification Fine droplet Microchannel array Scale up Silicon chip 



This work was supported by the Food Nanotechnology Project of the Ministry of Agriculture, Forestry, and Fisheries of Japan. The authors appreciate Ms. Chieko Takahashi, National Food Research Institute, for her assistance with experiments.


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Food Engineering DivisionNational Food Research Institute, NAROTsukubaJapan
  2. 2.EP Tech Co., Ltd.HitachiJapan
  3. 3.Graduate School of Life and Environmental SciencesUniversity of TsukubaTsukubaJapan

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