(580b) Temperature-Sensitive Polymer-Gold Nanocomposites as Intelligent Therapeutic Systems

The small size and unique properties of nanoparticles make them an ideal in vivo delivery system for the treatment of a wide variety of diseases including cancer, diabetes, multiple scleroses, and many others. These systems have the ability to safely localize and release therapeutic levels of potent drugs, such as chemotherapy agents, thereby lowering systemic doses, reducing side effects, achieving higher patient compliance and improved quality of life. This paper focuses on the development of a novel drug delivery nanocomposite system which synergistically combines the aspects of both intelligent response and therapeutic control into a single intelligent therapeutic system.

Intelligent temperature-sensitive interpenetrating polymer network (IPN) nanoparticles were formulated using poly(acrylic acid) (PAA) and poly(acrylamide) (PAAm). These polymers exhibit a unique positive sigmoidal swelling transition which makes them an ideal on/off mechanism for therapeutic release. Monodisperse PAA/PAAm IPN nanospheres where synthesized using a water in oil emulsion polymerization technique. The swelling behavior of these nanospheres with temperature was then characterized using dynamic light scattering.

Therapeutic control of these systems was then achieved by the incorporation of gold nanoshells at the core of the IPN nanoparticles. These nanoshell cores were specifically designed to absorb near infrared light because of its high transmission rate and penetration depth in tissue. The final polymer-gold nanocomposite systems were then exposed to a NIR light source which was absorbed and converted to heat by the nanoshells and is used to trigger the swelling of the surrounding IPN particles.

The combination of these two nanoparticles into a single intelligent therapeutic system will allow the external control of in vivo therapeutic release and treatment regimen.

This work was supported by a National Science Foundation Integrative Graduate Education and Research Traineeship (IGERT) Fellowship (to D.E.O.).