Fast solvent-driven micropump fabricated by two-photon microfabrication

A solvent-driven micropump was developed using three-dimensional two-photon microfabrication. The actuation of micropump is utilizing the bending behavior of hydrogel film under asymmetric solvent-stimulus. The micropump could absorb and discharge fluid reversibly by simply alternating solvent composition. Contributing to the thin hydrogel film with the thickness of 2.5 mu m, the response time was significantly improved to 0.17 s. The discharge capacity of fluid was estimated to be as low as 9.2x10(-2) pL. The pumping of such ultra-low-volume fluid will be useful for further miniaturization of micro-nanofluidic devices.