Unlocking Spatiotemporal Dynamics: Precise Dual-Modal Bioimaging of Endogenous c-MYC mRNA in Tumors via a...

Fluorescence bioimaging technology is widely applied in the biomedical field. However, single-modal fluorescence bioimaging faces limitations such as autofluorescence interference, inability for long-term bioimaging, and insufficient tissue penetration. Therefore, there is an urgent need to develop synergistic multimodal bioimaging techniques. This study for the first time proposed a novel catalytic hairpin assembly (CHA)-activated ZGMD nanoplatform for precise spatiotemporal bioimaging of endogenous c-MYC mRNA (c-MYC) by two-photon fluorescence resonance energy transfer (TP-FRET) and afterglow resonance energy transfer (ARET) bioimaging in tumors. ZGMD combined Zn₂GeO₄:Mn nanorods (ZGO:Mn), which have two-photon fluorescence and afterglow luminescence properties, with CHA-activated nucleic acid probes (H1 and H2-TAM). When ZGMD was delivered to tumors with high expression of c-MYC, the CHA reaction was triggered, thereby enabling dual-modal bioimaging of endogenous c-MYC by TP-FRET and ARET bioimaging. Satisfactorily, ZGMD achieved highly sensitive c-MYC detection with a limit of detection (LOD) as low as 39 pM and a 5.4-fold amplification ratio signal in vitro. Under TP excitation, ZGMD showed a tumor tissue penetration depth of 440 μm. Additionally, ZGMD significantly reduced autofluorescence and enabled long-term bioimaging by ARET. ZGMD achieved a signal-to-background ratio (SBR) of 291 for endogenous c-MYC by ARET bioimaging in vivo, and the afterglow signal of ZGMD was observed within 6 min in mice after preirradiation, which unlocked spatiotemporal dynamics of dual-modal bioimaging. Importantly, the ZGMD nanoplatform could visualize the dynamic fluctuations of endogenous c-MYC within tumors by dual-modal spatiotemporal bioimaging, providing a noninvasive tool for real-time assessment in disease diagnosis and cancer therapy.