Article

Mapping of fluidic mixing in microdroplets with 1 micros time resolution using fluorescence lifetime imaging.

Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom.
Analytical Chemistry (impact factor: 5.86). 03/2010; 82(9):3950-6. DOI:10.1021/ac100055g pp.3950-6
Source: PubMed

ABSTRACT Microdroplets generated in microfluidic channels hold great promise for use as substrates in high-throughput chemical and biological analysis. These water-in-oil compartments can serve as isolated reaction vessels, and since they can be generated at rates in excess of 1 kHz, thousands of assays can be carried out quickly and reproducibly. Nevertheless, sampling the large amount of information generated from these platforms still remains a significant challenge. For example, considering the high droplet generation rates and velocities, reproducibility and micrometer resolution are challenging requirements that must be fulfilled. Herein we combine confocal fluorescence lifetime imaging microscopy with a statistical implementation that permits the analysis of mixing phenomena within microdroplets with a temporal resolution of 1 mus. Importantly, such exquisite resolution is only possible as a result of the large number of droplets sampled and their high structural reproducibility.

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Keywords

1 kHz
 
confocal fluorescence lifetime imaging microscopy
 
droplet generation rates
 
droplets sampled
 
exquisite resolution
 
high-throughput chemical
 
large amount
 
microdroplets
 
microfluidic channels
 
phenomena
 
rates
 
significant challenge
 
statistical implementation
 
substrates
 
temporal resolution
 
velocities
 
water-in-oil compartments