To make the selective sorting of target cells in a multicomponent solution possible, the first step is to use an antigen–antibody reaction to attach antibody-immobilized nanobeads to the surfaces of target stem cells. Later, the resulting nanobead/stem cell compounds are trapped and separated from the mixture by applying other technologies. Creating the compounds makes this subsequent separation possible. To effect the actual separation, a microchannel with multiple electric strips is designed on a silicon substrate and is fabricated with the microelectromechanical systems technology. A local dielectrophoretic force, obtained from nonuniform electric fields, is used to manipulate and trap the compounds in a continuous flow. The experimental studies show that the compounds incur a local dielectrophoretic field when they are suspended in a continuous flow (Re=5.0) (Re=5.0) and are exposed to ac fields at a 500 kHz frequency. Using this device, the strip electrodes provide a local dielectrophoretic field strong enough to manipulate and attract nearby compounds in a continuous flow. Key Words bioelectric phenomena biomedical electrodes bioMEMS cellular transport electrophoresis microchannel flow molecular biophysics nanobiotechnology silicon
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