METHOD AND DEVICE FOR CONTROLLING ELECTOOSMOTIC FLOW BY USING LIGHT

摘要

Electroosmosis is an effective way to move fluids in microfluidic devices. The process is driven by the interaction of a double-layer formed at the surface of the fluid in a microspace of the device and the electric field parallel with the surface. Surface conductivity of light sensitive surfaces can be modified by light and thereby the flow pattern of the fluid can be manipulated. The invention relates to a microfluidic device and method to move fluids by electroosmosis and to manipulate flow of the fluid, wherein at least a part the surface adjacent to the fluid driven by electroosmosis is made of a light sensitive material, the surface conductivity of which is modified by changing illumination thereof, thereby flow of the fluid can be influenced. The invention can be used for example in microfluidic channels to manipulate flow velocity, for the preparation of microfluidic switches and mixers or "lab-on-a-chip" devices.