Micro Thermal Lab in a Droplet Available to Purchase

Droplet-based microfluidic system has the potential to provide a high throughput platform for applications in chemical and biological analysis. In this report, the concept of micro thermal lab in a droplet was proposed. A droplet of room temperature liquid-metal (Gallium-base alloy) was used to perform the thermal experiments. By applying controllable heating power, the liquid-metal droplet worked as an electrical resistor, generating Joule heat to accurately control its temperature. A proportional-integral-derivative (PID) temperature controller was used to control the heating power. Because the liquid-metal droplet has high surface-area-to-volume ratio and high thermal conductivity, it can be cooled down rapidly just by natural convection when left in atmosphere with the heating power switched off. Because of its small heat capacity and high heat conductivity, the liquid-metal droplet has rapid thermal response and uniform temperature distribution inside, which is ideal for a thermal experiment. This liquid-metal droplet can work as a micro thermal lab, which can offer a well-programmed, easily controllable, and thermally uniform microenvironment for on-chip chemical and biological analysis, such as PCR, cell culture and so on.