NIR-LIGHT RESPONSIVE BIOCOMPATIBLE COMPOSITES FOR ON-DEMAND HEALING AND RELEASE

Stimuli responsive biomaterials have a major role in many biomedical applications owing to their ability to change their physical state in response to an external stimuli. Among the diverse stimuli existing, light is of particular interest since it possesses many advantages, i.e. its parameters are easy to manipulate, and the procedure is safe and rapid. Despite their great potential, these materials are currently limited by the toxicity of the light triggered molecules and/or their by-products, or by the wavelength that is used to trigger them. Here we design, a unique system based on star-shaped biocompatible copolymers with tunable low melting point, incorporated with gold nanoshells (GNS). Upon near infrared (NIR) irradiation, these materials respond by undergoing a melting process and hence a shape transformation. We have successfully synthesized a series of multi-armed polyethylene glycol and caprolactone copolymers to create a biodegradable system of biocompatible copolymers. Characterization by chemical and physical properties showed an increase in melting temperatures with increasing molecular weights. The effects of variable irradiation parameters on matrix morphology, melting time, mechanical properties, and release profiles in response to NIR irradiation was examined as well as in-vitro system’s cytotoxicity. This NIR responsive concept has a great potential in biomedical devices and applications such as drug delivery, repairable tissue scaffolds and tissue adhesives.