Boundary Effect on Reflected Ultrasound Signals from Adherent Bubbles

An experimental apparatus for the analysis of the ultrasonic dynamics of bubbles on a surface is presented, together with preliminary data. Microbubbles offer the potential for targeted imaging and drug delivery utilising ultrasound technology free of ionizing radiation. Despite the development of many theoretical models, few experiments have been reported that differentiate the signals of adherent and non-adherent microbubbles under different boundary conditions. In this study, experiments were designed to capture the fundamental frequency response from freely flowing and adherent bubbles on different boundary conditions. Preliminary data suggested that while bubbles were adhered to an elastic boundary, strong reflections occurred compared to the control; and that while bubbles were adhered to a rigid boundary, weak reflections occurred compared to the control.