Patent attributes
A gravity-driven apparatus and method control the flow order of reactants in microfluidic devices which are employed in a microfluidic chip. The gravity-driven apparatus flow order control mainly comprises a plurality of reactant chambers arranged at different heights, a plurality of flow-control microchannels, and a reaction chamber having a winding collection microchannel. Each reactant chamber has an air-in vent. Each pair of neighboring flow-control microchannels has a U-shaped structure connecting the pair of neighboring flow-control microchannels. To activate the microfluidic device, the device is placed in an inclining or standing position and the air-in vents are unsealed. This method enhances the reliability of flow order control for multiple reactants. It can be built in a microfluidic chip, and does not use any actuating power or element. Therefore, it is low in energy-consumption, low in manufacturing cost and free of pollution.
