(151e) Plasmonic Nanomaterials for Tissue Sealing and Radiation Dosimetry

The ability to modulate electromagnetic radiation has diverse applications in biotechnology and medicine. Plasmonic nanoparticles (e.g. gold or silver nanoparticles) can efficiently absorb and scatter incident radiation, which makes them useful in biological imaging and therapeutics. In this presentation, I will discuss the use of plasmonic nanoparticles in tissue sealing and radiation sensing and dosimetry. Gold and silver nanoparticles, were incorporated within polypeptide matrices, leading to the formation of laser-activated tissue-integrating sealant (LATIS) nanomaterials. Irradiation of these materials with non-ionizing laser light facilitated a photothermal response, which, in turn, resulted in rapid, fluid-tight sealing of ruptured intestinal tissue ex-vivo and incised skin in live mice. As a second application, we demonstrate the use of gold nanoparticles as indicators of ionizing radiation at doses used in clinical radiotherapy. Irradiation of colorless gold salt formulations with ionizing photons (X-rays) and protons resulted in the formation of gold nanoparticles which rendered a visible color change to the liquid dispersion or an encapsulating gel. The intensity of the color formed was a function of the radiation dose employed, and was used to calibrate this nanoscale dosimeter. This technology was further extended for the detection of ionizing radiation doses delivered to specific regions in a spatially resolved manner, which opens up possibilities to detect “hot spots” in tissues. The efficacy of this novel dosimetry device was evaluated using clinical anthropomorphic phantoms and in animals. Our studies demonstrate that plasmonic nanomaterials can further advance the use ionizing and non-ionizing radiation in diverse clinical applications including tissue sealing and repair, and cancer radiotherapy.