Anti-inflammatory/infection PLA nanoparticles labeled with technetium 99m for in vivo imaging

Despite advancements in treatment of infectious diseases, opportunistic pathogens continue to pose a worldwide threat. Identifying a source of infection/inflammation is often challenging which highlights the need of improved diagnostic agents. Using a model of local S. aureus infection, here we evaluated the potential of betamethasone or dexamethasone loaded in poly (lactic acid) nanoparticles and radiolabeled with 99mTc to detect an infection/inflammation site in vivo. A betamethasone and dexamethasone nanoparticles (NPs) with 200 and 220 nm in size, respectively, were created with a 98% 99mTc radiolabeling efficiency. When injected in infected mice, betamethasone NPs presented a higher accumulation in the infected hind paw in comparison with dexamethasone NPs. Our results suggest that this nanosystem may be a valid nanoradiopharmaceutical for the detection of inflammation/infection foci in vivo.