A Microfabrication-Based Dynamic Array Cytometer

We have developed a microfabricated device for use in parallel luminescent single-cell assays that can sort populations upon the basis of dynamic functional responses to stimuli. This device is composed of a regular array of noncontact single-cell traps. These traps use dielectrophoresis to stably confine cells and hold them against disrupting fluid flows. Using quantitative modeling, we have designed traps with a novel asymmetric extruded-quadrupole geometry. This new trap can be physically arrayed and electrically addressed, enabling our cytometer. Situating an array of these traps in a microchannel, we have introduced cells into the array and demonstrated observation of fluorescent dynamic responses followed by sorting. Such a device has potential for use in investigating functional processes, as revealed by temporal behavior, in large numbers of single cells.