[ACS Sens.] Highly enriched, controllable, continuous aerosol sampling using inertial microfluidics
We report a novel microfluidic technique for sampling of aerosols into liquids. The two-phase fluid, sampling air and collecting liquid, forms a stratified flow in the curved microchannel. By passing fluids through the curved region, the particles are transferred from air into the liquid phase by the particle centrifugal and drag forces. This microfluidic-based aerosol-into-liquid sampling system, called the MicroSampler, is driven by particle inertial differences. To evaluate the physical particle collection efficiency of the MicroSampler, we used standard polystyrene-latex (PSL) particles ranging in size from 0.6 to 2.1 μm and measured particle concentrations upstream and downstream of the MicroSampler with an aerodynamic particle sizer. The cut-off diameter of particle collection was selected controlling the air flow velocity (microfluidic air flow of 0.6 L/min showed a particle collection efficiency of ~98% at a particle diameter of 1 μm), and continuous enriched particle sampling was possible for real-time post-processing application. With regard to biological collection efficiency, the MicroSampler showed superior microbial recovery (Staphylococcus epidermidis) compared to the conventional BioSampler technique. These results indicate that our MicroSampler can be used as a portable, cost-effective, simple and continuous airborne microorganism collector for applications in real-time bioaerosol detection.
Jeongan Choi, Seung Chan Hong, Woojin Kim, and Jaehee Jung ACS Sens., Just Accepted Manuscript DOI: 10.1021/acssensors.6b00753 Publication Date (Web): March 21, 2017 Copyright © 2017 American Chemical Society