Using photoresponsive nanoparticles loaded with dye, researchers at the Oregon State University College of Pharmacy and the Oregon National Primate Research Center have developed a way to identify and remove lesions associated with endometriosis, a common gynecological condition in women of childbearing age. The research team, which has expertise in nanomedicine and endometriosis, developed and evaluated the photoresponsive nanoagent to detect and eliminate unwanted endometrial tissue with photothermal ablation. The scientists used polymeric materials less than 100 nm in size, which were packed with a dye that could generate both a fluorescence signal and cell-killing heat under near-infrared light. The dye-loaded nanoparticles are injected into the body, where they fluoresce to show where the lesions are located. When the nanoparticles are exposed to infrared light, their temperature rises to 115 °F, and they emit enough heat to kill the lesions. “The heat is produced under near-infrared laser light that is harmless to tissue without the presence of the nanoparticles,” professor Oleh Taratula said. “The generated heat eradicates the endometrial lesions completely within a day or two.” Taratula said that one of the challenges for the team was finding nanoparticles that could accumulate primarily in endometriotic lesions without having a toxic effect on the body and without losing their imaging and heating properties. By using a clinically relevant animal model of endometriosis developed by professor Ov Slayden’s group at the Primate Research Center, the scientists showed that the nanoparticles constructed by the Taratula group could efficiently accumulate in endometrial tissue 24 hours after being administered. To advance the technology to human clinical trials, future studies will need to validate this treatment approach in animals that develop endometriosis similar to how it presents in humans. The research team has received a grant from the National Institutes of Health to evaluate the efficiency of the nanoparticles in macaques with endometriotic lesions. “We believe that our developed strategy can eventually shift the current paradigm for endometriosis detection and treatment,” Taratula said. “In general, nanomedicine has barely been explored for imaging and treatment of endometriosis. Our results validate that some fundamental principles of cancer nanomedicine can potentially be used for the development of novel nanoparticle-based strategies for treatment and imaging of endometriosis.” Roughly 10% of childbearing-age women will experience endometriosis, and 35% to 50% of women with pelvic pain and/or infertility suffer from the disorder. The research was published in Small (www.doi.org/10.1002/smll.201906936).