Thermal Control for Droplet-Based Microfluidics

This paper presents our recent works on thermal control for droplet-based microfluidics. Temperature dependent properties of liquids have been use for actuation and many other applications in droplet-based microfluidics. In analogy to an analog/digital electronic circuits, a droplet-based microfluidic system consists for three main subsystems: droplet formation (analog/digital converter), droplet manipulation (digital processing) and droplet merging (digital/analog converter). This paper will present our recent achievements in thermal control of droplet formation in different configurations such as T-junction and cross junction with integrated microheaters. Furthermore, results on droplet switching will be presented. The droplet switch represent basic logic gate that can be used to construct a more complex droplet-based digital network. Thermocapillary actuation of microdroplets in one-dimensional and two-dimensional microfluidic platforms will be presented. Both numerical and experimental results will be presented in this paper.