Drug Delivery

Joseph Badami

The development of microbubble systems has allowed the clinical application of ultrasound to progress as a viable option for medical imaging purposes due to the echogenic properties they demonstrate. Simultaneously, these structures serve as practical carriers for drug delivery purposes. These systems are typically limited, however, by overall size, which hinders their ability to navigate throughout specific vasculature, such as that often seen in tumors. Size and stability of these systems comes as a direct consequence of interfacial interactions that take place within shell components, thus, a greater understanding of these interactions could prove instrumental to the further development of the field. Polymeric materials show great promise as stabilizing agents since they can be finely controlled in both size and composition. This work investigates the fundamental aspects of bubble stabilization using polymeric materials to further enhance the lifetime associated with such bubbles. The fundamental phase behavior demonstrated by these shell materials are explored with an aim to determine the particular effects they invoke on the elasticity and stability of bubbles at sub-micron scales. Similarly, this work investigates how particular molecules (i.e. polymers, proteins) promote or influence curvature associated with bubbles at the micron scale. Lastly, the microstructure associated with such phase behavior is studied using microscopy techniques in order to gain a greater understanding of the interfacial ordering present.