Controllable vapor microbubbles for use in bioparticle actuation

Abstract

In this thesis, we present guidelines for using thermally formed microbubbles as a means of fluidic actuation. The use of microbubbles is attractive due to the simple fabrication and operation of such devices, however, prior work in this area was hindered by several issues inherent to vapor bubble formation that severely limited the reliability of bubble-based devices. It has been shown in this thesis that it is possible to control the location at which bubbles form and the size of the bubbles, as well as to achieve repeatable and reduced bubble formation temperature, and to create bubbles that collapse completely in less than 10 seconds. The achievement of controllable microbubbles makes possible many microfluidic applications, one of which we will demonstrate in this work. We have built a device that is capable of capturing, holding, and selectively releasing single bioparticles using microbubble actuation. This bioparticle actuator could be scaled into an array for the analysis of a large population of individual cells.