Manipulating fluids and fields In multimaterial fibers

Abstract

From conduits for fluid transport to the threads in highly absorbant textiles, high aspect ratio fibers and tubings have been used for thousands of years to manipulate fluids. The emergence of multimaterial thermal drawing as a method to fabricate fibers with precise spatial control of a broad range of materials, such as polymers and metals, enables the integration of new functionalities into these traditionally single material tools. In this thesis we investigate the use of thermally drawn fibers as a means to manipulate fluids and electric fields for various applications. As a conduit for fluids flowing in the axial direction of the fiber, we explore new regimes in inertial microfluidics by leveraging the geometric tunability of fiber channel cross-sections. By integrating electrodes onto the channel surface, we later design a microfluidic device capable of inertial-dielectrophoretic live/dead cell separation at throughputs as high as 100 5[mu]L/min. In addition, we show that UV-transparent hollow fibers can be used as templates to fabricate highly complex 3-D hydrogel microparticles with dielectrophoretic sub-particle localization. Finally, by integrating surface-interfaced porous structures into electrode-integrated fibers, we demonstrate fluid flow manipulation in the radial direction for application as a fiber sweat sensor.