The goal of this research was the development of a portable therapeutic device for the treatment of diabetes. A 3x3 cymbal array has been successfully tested in noninvasive insulin delivery experiments. The cymbal is a composite flextensional transducer constructed from a poled PZT ceramic and shaped metal endcaps that amplify the transducer motions by two orders of magnitude. Nine cymbals are wired in parallel and potted in polyurethane to form the flat panel arrays. When driven near resonance (20 kHz), the array generated a low intensity acoustic beam of 100 mW/cm(2). Animal experiments on hyperglycemic rats and rabbits demonstrated the ultrasonic enhancement of transdermal insulin delivery. (c) 2006 Springer Science + Business Media, Inc.