|Drop or Bubble on demand in a microfluidic chip
A novel technique of in-chip drop on demand has been developed to dispense individual picoliter to nanoliter drops directly in the liquid-filled channels, with precise size and timing control.
– Drops can be generated continuously at up to 2.5 kHz.
– Drops with volumes from 25 pL to 4.5 nL can be precisely generated by varying pulse shapes and nozzle sizes.
– At low dispense rate, the standard deviation of drop volumes is measured to be less than 2 %.
In addition to dispensing drops, the piezoelectric actuation technique can be used to dispense a single bubble on demand in the main channel.
Funding: NSF grants 0449269 and 0701729 and Columbia Medical School.