(594a) Stable Biomedical Colloids for Imaging Contrast Agents and Drug Delivery Systems

Colloidal systems have been studied extensively and intensively in the biomedical area for imaging contrast agents and drug delivery carriers. In this talk, I will discuss “biomedical colloids” that I have developed, light-activatable theranostic agents for ultrasound imaging-monitored controlled drug release. Our lab has developed light-activatable theranostic agents for long-term controlled drug release, with which drug release can be controlled and monitored by ultrasound imaging systems. The theranostic agents consist of gold nanorod-coated phase-transition double nanoparticles which encapsulate drug molecules. Our preliminary study has shown that the double nanoparticles are stable against aggregation, disruption, and passive drug leakage in physiological conditions. In addition, we have demonstrated phase-transition of the double nanoparticle to gas microbubbles which still encapsulate drug molecules upon a single pulse of near-infrared femtosecond laser, implying drug release can be controlled and monitored by ultrasound imaging systems. At the end of the talk, I would like to briefly mention about my other research projects using microvessels-on-a-chip. The projects are to study physicochemical effect of microbubble ultrasound cavitation on cellular uptake and to use the in vitro model as a theranostic platform.