title: Shear stress mapping in microfluidic devices by optical tweezers.
abstract: We present an optical tweezer sensor for shear stress mapping in microfluidic systems of different internal geometries. The sensor is able to measure the shear stress acting on microspheres of different sizes that model cell based biological operations. Without the need for a spatial modulator or a holographic disk, the sensor allows for direct shear stress detection at arbitrary positions in straight and curved microfluidic devices. Analytical calculations are carried out and compared with the experimental results. It is observed that a decrease in the microsphere size results in an increase in the shear stress the particle experiences.
authors.affiliation: Centre for Micro-Photonics, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Hawthorn, PO Box 218, Victoria 3122, Australia.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.forename: Daniel
authors.initials: D
authors.lastname: Day
authors.forename: Min
authors.initials: M
authors.lastname: Gu