Microfluidics and Nanofluidics

, Volume 7, Issue 2, pp 275–281 | Cite as

Refolding of β-galactosidase: microfluidic device for reagent metering and mixing and quantification of refolding yield

  • Sowmya Kondapalli
  • Brian J. Kirby
Short Communication


We have developed a device that uses microfluidic valves and pumps to meter reagents for subsequent mixing with application to refolding of the protein β-galactosidase. The microfluidic approach offers the potential advantages of automation, cost-effectiveness, compatibility with optical detection, and reduction in sample volumes as opposed to conventional techniques of hand-pipetting or using robotic systems. The device is a multi-layered poly(dimethylsiloxane) on glass device with automated controls for reagent aliquoting and mixing. Refolding experiments have been performed off-chip using existing protocols on the protein β-galactosidase and the refolding yield has been quantified on-chip using fluorescein di-β-d-galactopyranoside, a caged-fluorescent molecule. This work provides the potential to reduce the cost of drug discovery and realization of protein pharmaceuticals.


Protein refolding β-Galactosidase Combinatorial Microfluidic 



The authors would like to acknowledge useful discussions with Prof. David Putnam and the lab assistance of Mike Arszman, Dino Castellucci and Prashant Sundar.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Sibley School of Mechanical and Aerospace EngineeringCornell UniversityIthacaUSA

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