On-chip cell transportation based on vibration-induced local flow in open chip environment

We present a novel cell manipulation method based on vibration-induced flow in open-chip environment. By applying circular vibration to a chip having micropillar patterns on its surface, local whirling flow is induced around the micropillars. Therefore, by patterning micropillar array on a chip and applying the circular vibration to the chip, we can achieve cell transportation along the array in an open chip environment. We theoretically analyzed this phenomenon with a single micropillar, and experimentally evaluated behaviours of manipulated microbeads with two micropillars. We confirm there are different manipulation modes according to the pitch of micropillars. We designed the micropillar array for an oocyte transportation based on these evaluations. We succeeded in the transportation of oocytes with up to 35.6 μm/s and confirmed that the velocity can be changed by changing the frequency and amplitude of the applied vibration.