Time-resolved fluorescence imaging of solvent interactions in microfluidic devices.
We present the application of wide-field time-resolved fluorescence imaging methods for the study of solvent interactions and mixing in microfluidic devices. Time-resolved imaging of fluorescence polarization anisotropy allows us to image the local viscosity of fluorescence in three dimensions in order to directly monitor solvent mixing within a microfluidic channel. This provides a viscosity image acquisition time of the order of minutes, and has been applied to a steady-state laminar flow configuration. To image dynamic fluid mixing in real-time, we demonstrate high-speed fluorescence lifetime imaging at 12.3 Hz applied to DASPI, which directly exhibits a solvent viscosity-dependant fluorescence lifetime. These two methods facilitate a high degree of quantification of microfluidic flow in 3-D and/or at high speed, providing a tool for studying fluid dynamics and for developing enhanced microfluidic assays.
Benninger
Richard
R
Hofmann
Oliver
O
McGinty
James
J
Requejo-Isidro
Jose
J
Munro
Ian
I
Neil
Mark
M
Demello
Andrew
A
French
Paul
P