A microfluidic chip for formation and collection of emulsion droplets utilizing active pneumatic micro-choppers and micro-switches

Biomed Microdevices. 2008 Oct;10(5):749-56. doi: 10.1007/s10544-008-9186-3.

Abstract

The formation of emulsification droplets is crucial for many industrial applications. This paper reports a new microfluidic chip capable of formation and collection of micro-droplets in liquids for emulsion applications. This microfluidic chip comprising microchannels, a micro-chopper and a micro-switch was fabricated by using micro-electro-mechanical-systems (MEMS) technology. The microfluidic chip can generate uniform droplets with tunable sizes by using combination of flow-focusing and liquid-chopping techniques. The droplet size can be actively fine-tuned by controlling either the relative sheath/sample flow velocity ratios or the chopping frequency. The generated droplets can be then sorted to a specific collection area utilizing an active pneumatic micro-switch formed with three micro-valves. Experimental data showed that the olive oil and sodium-alginate (Na-alginate) droplets with diameters ranging from 3 mum to 70 mum with a variation less than 14% is successfully generated and collected. The development of this microfluidic system can be promising for emulsion, drug delivery and nano-medicine applications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alginates / chemistry
  • Alginates / ultrastructure
  • Emulsions / analysis*
  • Emulsions / chemistry*
  • Equipment Design
  • Microfluidic Analytical Techniques / instrumentation*
  • Microfluidic Analytical Techniques / methods
  • Microfluidics / instrumentation*
  • Olive Oil
  • Plant Oils / chemistry
  • Pressure
  • Water / chemistry

Substances

  • Alginates
  • Emulsions
  • Olive Oil
  • Plant Oils
  • Water