Nanoscience and Nanotechnology Commons^™

Negative Dielectrophoretic Capture Of Bacterial Spores In Food Matrices, Mehti Koklu, Seungkyung Park, Suresh D. Pillai, Ali Beskok

Mechanical & Aerospace Engineering Faculty Publications

A microfluidic device with planar square electrodes is developed for capturing particles from high conductivity media using negative dielectrophoresis (n-DEP). Specifically, Bacillus subtilis and Clostridium sporogenes spores, and polystyrene particles are tested in NaCl solution (0.05 and 0.225 S/m), apple juice (0.225 S/m), and milk (0.525 S/m). Depending on the conductivity of the medium, the Joule heating produces electrothermal flow (ETF), which continuously circulates and transports the particles to the DEP capture sites. Combination of the ETF and n-DEP results in different particle capture efficiencies as a function of the conductivity. Utilizing 20 μm height DEP chambers, “almost complete” and …