Paper BI-TuP7
Ceria-Gold-Chitosan Nanosystem with Improved Redox Activity and Enhanced Imaging

Tuesday, October 30, 2012, 6:00 pm, Room Central Hall

Research advances in nanoparticles constructs intended for biomedical applications have proved to be of major importance. This often presents serious challenges in terms of imaging or tracking of the nanoparticles. Our research aims at developing a system that has the effective characteristics of therapeutics and imaging modality. It is well known that Reactive oxygen species (ROS) and nitrogen species play a critical role in many oxidative stress associated disorders like cancer, neurodegeneration, radiation induced tissue damage. Ceria nanoparticles (CNPs) have proved to be potential redox active radical scavenging agents which also exhibit superoxide dismutase and catalase mimetic activity. These nanoparticles can potentially act as antioxidant which is attributed to its redox nature of switching the oxidation states from +3 to +4 mediated at the oxygen vacancies on the surface. Recent research has shown progress in the study of enhancing the contrast in imaging using gold nanoparticles by various microscopy techniques such as TEM, Computed tomography (CT) etc. Its marker ability is attributed to the strong plasmon enhanced absorption and increased light scattering ability which gives detailed information of the location of gold particles by combining optical and electronic microscopy. It is also proven to be non toxic and biocompatible in vivo. Our research attempts on providing a formulated coupling of the above notions to form a CNP-Chitosan-Gold integrated system. Addition of Chitosan helps in the reduction of HAuCl₄ to form gold nanoparticles and this polymer also enables the biocompatibility of the imaging agent. The activity of CNPs can be improved by surface modification through selective functionalization thereby enhancing the redox behavior and stability of the system.