(545e) Development of Nanoparticles for in Vivo Imaging

Nanotechnology is gaining importance in biomedical applications for drug delivery and imaging. It has the potential to enhance the efficacy and specificity of drugs and imaging agents and allow for a more detailed understanding of biological systems. For e.g., in cancer therapy the challenges include early disease detection and targeted delivery of imaging and therapeutic agents to the tumor region. Most cancer drugs do not discriminate between normal and diseased tissues causing undesirable side effects. A potential approach to improved therapeutic efficacy of these drugs is better drug delivery system that can target tumors with high specificity. Non-invasive imaging modalities offer a potential framework for developing such drug delivery systems and can provide spatio-temporal information of the delivery and release of model imaging agents at diseased sites. In this study, we use BLI to develop novel drug delivery systems based on encapsulated luciferin nanoparticles, with luciferin as the model drug. Nanoparticles of luciferin have been formed using a supercritical fluid antisolvent system (SAS), and process conditions have been optimized for particle size and particle size distribution. Due to the unique properties of supercritical carbon dioxide, no purification or drying steps are needed, and the process is compatible with bioactive compounds, such as proteins. The particles have also been encapsulated, using the SAS process with biodegradable polymers such, as poly(lactic acid) (PLA) and poly(DL-lactide-co-glycolide) (PLGA), for controlled-release of drug and to protect active compounds from degradation during storage and delivery. A transgenic reporter mouse that expressed luciferase ubiquitously throughout the mouse is used to study the biodistribution of the model drug, luciferin. Luciferin is delivered as a modified nanoparticle either by inhalation or intravenously, and its biodistribution imaged noninvasively.