Automated Microfluidic System with Active Mixing Enables Rapid Analysis of Biomarkers in 5 μL of Whole Blood

We
developed a microfluidic device for the rapid analysis of biomarkers
in small volumes of whole blood. This device includes an onboard plasma
separation module connected to a downstream bioanalysis module in
which plasma mixes with reagents and the results of a colorimetric
assay are recorded. Actuation of onboard microvalves within a bioanalysis
module creates active mixing conditions that allowed us to achieve
solution homogeneity within 5 min. To demonstrate utility, we carried
out glucose detection in our device. With 5 μL of whole blood
as an input, our microfluidic device enabled a time-to-answer of 10
min with a limit of detection of 0.21 ± 0.04 mM for glucose.
This device has immediate applications for rapid and sensitive monitoring
of hypoglycemia at the point of care (POC). Furthermore, our automated
microfluidic device represents a platform technology that may be used
to detect other biomarkers in whole blood.