A microfluidic device and method is provided for handheld diagnostics and assays. The device includes a base having outer surface and a channel therethough for receiving fluid therein. The channel has input and output ports communicating with the outer surface. A lid is also provided. The lid has an outer surface, a first well having a port communicating with the outer surface of the lid, and a second well having a port communicating with the outer surface. The lid moveable between a first disengaged position and a second engaged position wherein the first port of the lid is adjacent the input port of the channel and the second port is adjacent the output port of the channel.