1 research outputs found
Hands-Off Preparation of Monodisperse Emulsion Droplets Using a Poly(dimethylsiloxane) Microfluidic Chip for Droplet Digital PCR
A fully
autonomous method of creating highly monodispersed emulsion
droplets with a low sample dead volume was realized using a degassed
poly(dimethylsiloxane) (PDMS) microfluidic chip possessing a simple
T-junction channel geometry with two inlet reservoirs for oil and
water to be loaded and one outlet reservoir for the collection of
generated droplets. Autonomous transport of oil and water phases in
the channel was executed by permeation of air confined inside the
outlet reservoir into the degassed PDMS. The only operation required
for droplet creation was simple pipetting of oil and aqueous solutions
into the inlet reservoirs. Long-lasting fluid transport in the current
system enabled us to create ca. 51,000 monodispersed droplets (with
a coefficient of variation of <3% for the droplet diameter) in
80 min with a maximum droplet generation rate of ca. 12 Hz using a
PDMS chip that had been degassed overnight. With multiple time-course
measurements, the reproducibility in the current method of droplet
preparation was confirmed, with tunable droplet sizes achieved simply
by changing the cross-sectional dimensions of the microchannel. Furthermore,
it was verified that the resultant droplets could serve as microreactors
for digital polymerase chain reactions. This hands-free technique
for preparing monodispersed droplets in a very facile and inexpensive
fashion is intended for, but not limited to, bioanalytical applications
and is also applicable to material syntheses