A cyanine-modified upconversion nanoprobe for NIR-excited imaging of endogenous hydrogen peroxide signaling in vivo

Abstract Endogenous hydrogen peroxide is an important parameter associated with cellular signal transduction and homeostasis. However, abnormal H 2 O 2 regulation in live systems has been implicated in many pathological conditions. Monitoring this signal in live systems is essential but challenging because current H 2 O 2 probes are impractical for efficient bio-imaging due to UV/visible light as the excitation source. We herein present a novel design based on an organic fluorophore-attached lanthanide-doped upconversion nanoprobe (CYD1-UCNPs) for selective UCL detection of H 2 O 2 . This nanoprobe represents the next-generation imaging tool that features a robust UCL “turn-on” response to H 2 O 2 with NIR-excited ratiometric signals and has potential applications in ratiometric UCL imaging of endogenous H 2 O 2 generating in living cells and whole-body animals.