Patent ID: 11148136

Abstract:
Methods and apparatus for driving flow in a microfluidic arrangement are provided. In one disclosed arrangement, the microfluidic arrangement comprises a first liquid held predominantly by surface tension in a shape defining a microfluidic pattern on a surface of a substrate. The microfluidic pattern comprises at least an elongate conduit and a first reservoir. The area of contact between the substrate and a portion of the first liquid that forms the elongate conduit defines a conduit footprint. The area of contact between the substrate and a portion of the first liquid that forms the first reservoir defines a first reservoir footprint. The size and shape of each of the conduit footprint and the first reservoir footprint are such that a maximum Laplace pressure supportable by the first liquid in the elongate conduit without any change in the conduit footprint is higher than a maximum Laplace pressure supportable by the first liquid in the first reservoir without any change in the first reservoir footprint. A delivery member having an internal lumen leading to a distal opening through which liquid can be delivered is provided. Liquid is pumped into the microfluidic pattern through the distal opening while the distal opening is held in a delivery position. The delivery position is such that the liquid enters the microfluidic pattern via the elongate conduit and drives a flow of liquid into the first reservoir.