Joule heating monitoring in a microfluidic channel by observing the Brownian motion of an optically trapped microsphere

摘要: Electric fields offer a variety of functionalities to Lab-on-a-Chip devices. The use these often results in significant Joule heating, affecting the overall performance system. Precise knowledge temperature profile inside microfluidic device is necessary evaluate implications heat dissipation. This article demonstrates how an optically trapped microsphere can be used as probe monitor heating Brownian motion bead at room compared with when power dissipated gives estimate increase specific location channel. We demonstrate this method solutions different ionic strengths, and establish precision 0.9 K accuracy 15%. Furthermore, it demonstrated that transient processes monitored technique, albeit limited time resolution.