title: A microfluidic concentrator array for quantitative predation assays of predatory microbes.
abstract: We present a microfabricated concentrator array device that makes it possible to quantify the predation rate of Bdellovibrio bacteriovorus, a predatory microbe, toward its prey, Escherichia coli str. MG1655. The device can accumulate both prey and predator microbes sequentially within a series of concentrator arrays using the motility of the microbes and microfabricated arrowhead-shaped ratchet structures. Since the device can constrain both prey and predator cells within 200 pL chambers at a desired range of cell densities, it was demonstrated that the device cannot only enhance the possibility of studying predation processes/cycles directly at a single cell level but can also quantify the predation rates indirectly by measuring the time-dependent fluorescent intensity signals from the prey. Furthermore, the device can produce a wide range of initial prey to predator density ratios within various concentrator arrays through the use of microfluidic mixer structures on a single array chip, which allows us to study many different conditions with a single set of cultures, and quantitatively characterize the predation behaviour/rate. Lastly, we note that this novel concentrator array device can be a very powerful tool facilitating studies of microbial predations and microbe-microbe interaction and may be broadly used in other microbial biotechnological applications.
authors.affiliation: School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology, Banyeon-ri 100, Ulsan, 689-798, Republic of Korea.
authors.forename: Seongyong
authors.initials: S
authors.lastname: Park
authors.forename: Dasol
authors.initials: D
authors.lastname: Kim
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Mitchell
authors.forename: Taesung
authors.initials: T
authors.lastname: Kim
mesh_terms: D001501:Bdellovibrio / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods