Application of fluorescence correlation spectroscopy for velocity imaging in microfluidic devices.
In this paper we present and demonstrate a technique for mapping fluid flow rates in microfluidic systems with sub-micrometer resolution using confocal microscopy in conjunction with fluorescence correlation spectroscopy (FCS). Flow velocities ranging from approximately 50 microm/s to approximately 10 cm/s can be recorded using fluorescent polymer nanospheres as fluid motion tracers. Velocity profiles and images of the flow in poly(dimethylsiloxane)-glass microchannels are presented and analyzed. Using the method, velocity images along the horizontal (top view) and vertical planes within a microdevice can be obtained. This is, to our knowledge, the first report of FCS for producing velocity maps. The high-resolution velocity maps can be used to characterize and optimize microdevice performance and to validate simulation efforts.
Kuricheti
Kalyan K
KK
Chemical Engineering Department, FAMU-FSU College of Engineering, Tallahassee, Florida 32306, USA.
Buschmann
Volker
V
Weston
Kenneth D
KD
D002626:Chemistry, Pharmaceutical / Q000379:methods; D044085:Microfluidics / Q000379:methods*; D018613:Microscopy, Confocal / Q000379:methods; D008856:Microscopy, Fluorescence; D012212:Rheology / Q000379:methods*; D013050:Spectrometry, Fluorescence / Q000379:methods*