Development of Manganese Carbonyl Loaded Upconversion Nanoparticles for Near-Infrared-Triggered Carbon Monoxide and Mn2+ Delivery

Photoactivatable carbon monoxide-releasing molecules (CORMs), typically based on transition-metal carbonyl complexes, have reliance on activation by UV or visible light that restricts their biomedical applications. To address this limitation, a near-infrared (NIR)-responsive nanoplatform is presented based on upconversion nanoparticles (UCNPs) loading with manganese carbonyl complex Mn 2 (CO) 10 that concurrently releases CO and manganese ion (Mn 2+ ). With the UCNPs, the more tissue-penetrable NIR is used to locally generate UV light for photodecomposition of Mn 2 (CO) 10 into CO and manganese oxide (MnO X ), after which MnO X is reduced to Mn 2+ by the overexpressed glutathione in cancer cells. Moreover, the released Mn 2+ can serve as a magnetic resonance imaging contrast agent to monitor the NIR-controlled corelease of CO and Mn 2+ in real time. Therefore, this nanoplatform can provide a potential strategy for NIR-enabled spatiotemporally release of CO and Mn 2+ , enhancing the controlled delivery and biomedical application of CORMs.