Study of Liquid Metal Based Thermal Micro-System for On-Chip Cell Culture Purpose

Room temperature liquid metal has been widely used in many MEMS applications, such as integrated heaters, sensors, electrodes and stretchable wires. Injecting the liquid metal into microchannels provides a simple, rapid and low-cost way to fabricate micro heaters and sensors. The liquid-metal-filled microstructures can be designed in any shape and easily integrated into micro devices. In this study, a liquid-metal based thermal micro-system was proposed for on-chip cell culture purpose. The thermal micro-system consisted of two same microchannels filled with the liquid metal as electrical heaters. At the same time, the heater also worked as a resistance temperature sensor to control the heating process. The temperature sensor was calibrated from 20 °C to 70 °C to give an accurate temperature control for the microsystem. To justify whether this micro-system is capable of providing a uniform temperature distribution, Rhodamine B was filled into the micro cell culture chamber of interest to monitor the temperature distribution. Thermal analysis was numerically carried out to reveal the temperature field of the chip. This thermal micro-system has great potential use in many microfluidic applications, such as on-chip PCR, temperature gradient focusing, protein crystallization or chemical synthesis.