Single-chamber micromixing and PCR. (A) Sequential process of pipetting, micromixing, and PCR. After injecting solutions, their streams fill the chamber by capillarity. Upper- and lower-level heaters embedded in a membrane are used for micromixing and PCR, respectively. Natural convection induces micromixing. (B) Microfluidic cartridge. The microfluidic cartridge is a disposable component, which has simple 2-D shape microchannels and a chamber where the height is 180 μm. Sample transport is driven by capillarity in the microfluidic cartridge. The PDMS cartridge slab is coated with parylene for preventing evaporation of solutions. A stainless-steel film of 8 μm thickness is used as the sealing membrane at the bottom of the chamber. (C) Microfabricated heating-instrument. The microfabricated heating-instrument is a component for repeated use that incorporates temperature sensors and heaters within the membrane. The single and dual heaters are for micromixing, and the reaction heater is for PCR. (D) Assembly of heating instrument and microfluidic cartridge components. Scale bars, 3 mm.