Power-free pumping

Japanese scientists have developed a new power-free pumping method for poly(dimethylsiloxane) (PDMS) microfluidic chips. Until now, most microfluidic devices have required external power sources to move fluids, complicating what should be simple, user-friendly technology.

PDMS is fast becoming a standard material for microfluidics because of its easy fabrication. Kazuo Hosokawa and co-workers from RIKEN and the National Institute of Advanced Industrial Science and Technology (AIST) exploited another important property of PDMS, its high gas solubility, to devise a simple procedure for performing liquid-liquid reactions. The PDMS chip is first de-gassed in a vacuum before the liquid samples are added to the inlet reservoirs. The chip gradually absorbs air, which then makes the samples flow through the system, allowing reactions and analysis.

Hosokawa and co-workers have demonstrated the potential of their technique by using it to perform gold nanoparticle-based DNA analysis. They hope the method will be useful for point-of-care and single-use analytical devices.

Rowena Milan