Activatable organic upconversion nanoprobe for bioimaging of monoamine oxidase B in Parkinson’s disease

Monoamine oxidase B (MAO-B) activity has been observed abnormally elevated in Parkinson's disease patients and can be used as a potential biomarker. Herein, we report an activatable frequency upconversion luminescence (FUCL) MAO-B nano-probe (NIR-MNP) capable of highly specific and real-time MAO-B imaging in biological samples. The turn-on FUCL effect is beneficial to obtaining high-quality imaging and penetrating tissue to achieve in vivo imaging, making it stand out from the existing probes. Moreover, we used NIR-MNP to confirm the role of MAO-B inhibitor in delaying Parkinson's disease (PD) progression in mouse PD models through bio-imaging technique in vivo. Finally, our study may offer a visual way help researchers to gain further insight into the involvement of MAO-B in PD onset and progression in animals.