Albany 2015:Book of Abstracts

Albany 2015
Conversation 19
June 9-13 2015
©Adenine Press (2012)

Inertial microfluidics for biofluid processing

Inertial microfluidics is a new field of study which involves behaviors and properties of the interactions among fluids, particles and structures in microfluidic channels where both inertia and viscosity become equivalently important (Chung and Papautsky 2014; Di Carlo 2009) In conventional microfluidics, fluid inertia is ignored because the associated Reynolds number is close to zero because of small channel length and low flow velocity. Near-zero Reynolds number flow characteristics reduces the Navier-Stokes equations to the Stokes equations which can describe general microchannel flow behaviors. However, when Reynolds numbers become finite, which can be seen often in microfluidics, the Stokes approximation is no longer valid, and flow motions significantly deviate from Stokes flow. There are two consequent inertial effects found in microchannels:
(i) Inertial particle migration and
(ii) Geometry induced secondary flows
as shown in the figure.


Two unique inertial effects found in microchannels can be of great practical use particularly in high-throughput biofluid processing. A high-speed cell process is an extremely crucial task because the process speed directly correlates with biological sample volumes (i.e. throughput). In fact, there are increasing demands for cell processing techniques which can deal with large volumes of biofluids (on the order from mL to L), such as blood, pleural fluid and urine (Jin et al. 2014; Hyun and Jung 2014; Mach et al. 2013) for clinical applications. In order to process large volumes of biofluids rapidly in microfluidics, we take advantage of mentioned two inertial effects in microchannels. For instance, we demonstrated inertial focusing of mammalian cells and microparticles for highly ordered lattices in a continuous flow to enhance clinical utility of microfluidic systems (Chen et al. 2014; Chung et al. 2013a; Chung et al. 2013b). Also, we utilize fluid inertia for a real-time cancer diagnosis through high-throughput cell deformability measurements as another example. Through this presentation, fundamentals of inertial microfluidics and its biomedical applications will be discussed.


    Chen Y, Chung AJ, Wu TH, Teitell MA, Di Carlo D, Chiou PY (2014) Pulsed Laser Activated Cell Sorting with Three Dimensional Sheathless Inertial Focusing. Small 10 (9):1746-1751.

    Chung AJ, Gossett DR, Di Carlo D (2013a) Three Dimensional, Sheathless, and High-Throughput Microparticle Inertial Focusing Through Geometry-Induced Secondary Flows. Small 9 (5):685-690.

    Chung AJ, Papautsky I (2014) Emerging opportunities from inertial microfluidics for biomedical studies. (In preparation).

    Chung AJ, Pulido D, Oka JC, Amini H, Masaeli M, Di Carlo D (2013b) Microstructure-induced helical vortices allow single-stream and long-term inertial focusing. Lab Chip 13 (15):2942-2949.

    Di Carlo D (2009) Inertial microfluidics. Lab Chip 9 (21):3038-3046.

    Hyun K-A, Jung H-I (2014) Advances and critical concerns with the microfluidic enrichments of circulating tumor cells. Lab Chip 14 (1):45-56.

    Jin C, McFaul SM, Duffy SP, Deng X, Tavassoli P, Black PC, Ma H (2014) Technologies for label-free separation of circulating tumor cells: from historical foundations to recent developments. Lab Chip 14 (1):32-44.

    Mach AJ, Adeyiga OB, Di Carlo D (2013) Microfluidic sample preparation for diagnostic cytopathology. Lab Chip 13 (6):1011-1026.

Aram J. Chung

Mechanical, Aerospace
and Nuclear Engineering
Troy, NY 12180

Ph: (518) 276-6449
Fx: (518) 276-6025