Conclusion
In this paper, we present a bacteria isolation method using
elasto-inertial microfluidics, consisting of a two turn spiral channel
design for separating viable bacteria from diluted blood at high
efficiency and throughput. In this work, we use viscoelastic buffer to
sheath the diluted blood sample to the outer wall of a spiral and
demonstrate for the first time that blood cells remain fully focused at
the outer wall throughout the entire spiral length while bacteria
continuously migrate due to the dean vortices for efficient separation.
The viable bacteria are recovered free of blood cells and readily
available for downstream analysis. In this work, we address one of the
main challenges of miniaturization for sepsis application: the trade-off
between separation efficiency and throughput. Here, we demonstrate
separation of E.coli from 1mL of blood in 40 minutes at an
efficiency of 82% using a label-free, passive method. The microfluidic
platform opens up possibilities of effectively and rapidly separating
viable bacteria from blood at throughputs unmatched using existing
microfluidics methods and should warrant clinical value as a stand-alone
sample preparation method in clinical settings.