187m Nanocomposites Based on Gold Nanorods and Thermally-Responsive Polymer Nanogels

Fedena Fanord and Vinay K. Gupta. Chemical & Biomedical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620

Advancements in nanotechnology have catalyzed the creation of functional nanocomposites tailored for diverse applications. Gold nanoparticles (GNP) are metal nanoparticles that have emerged from such innovation, possessing unique optical, electrical, magnetic and catalytic properties. Gold nanorods (GNR) are anisotropic GNPs that hold promise for sensing and diagnostic imaging applications owing to their absorption in the near infrared (NIR) spectral region. GNRs can be combined with polymers to form nanocomposites with enhanced properties. In our research, the focus has been to prepare novel nanomaterials by chemical coupling of GNR with a thermally responsive polymer, poly(N-isopropylacrylamide) (PNIPAM). Chemical coupling of the polymer nanogels to the gold nanorods can be detected due to the sensitivity of its plasmon absorption peak to changes in the dielectric environment. The goal is to exploit the optical properties of the GNR in tandem with the stimuli-responsive polymer for applications ranging from therapeutic treatment as well as diagnostic imaging. We will discuss our progress in surface modifying the GNR with an organic ligand that participates in covalent cross-linking with the PNIPAM chains to form polymer end-capped GNR composites. Characterization of the materials with UV-Vis and infrared spectroscopy, dynamic light scattering, and transmission electron microscopy (TEM) will be presented.