Continuous microfluidic airborne bacteria separation using dielectrophoresis

Airborne microbes such as bacteria are a threat to public health. To prevent and control such dangerous biological particles, robust and real-time detection systems are necessary. For direct and real-time detection of airborne microbes, samples must be collected and typically re-suspended in liquid prior to detection; however, environmental particles such as dust are also trapped in such samples. Therefore, the isolation of target bacteria or selective collection of microbes from unwanted non-biological particles prior to detection is of great importance. Dielectrophoresis (DEP), the translational motion of particles in non-uniform electric fields, is an emerging technique that can rapidly separate biological particles in microfluidics. In this paper, we propose a new method for the separation of airborne microbes using DEP with a simple and novel curved electrode design for separating bacteria in a solution containing beads or dust which is taken from an airborne environmental sample. As there has been little research on analyzing environmental samples using microfluidics and DEP, this work describes a novel strategy for a rapid and direct bioaerosol monitoring system.