Molecularly Engineered Dual-Lock Activatable NIR-II Fluorogenic Probe for Precision Tumor Resection and Real-Time Chemotherapy Response Monitoring

Despite advancements in multimodal cancer therapies, complete surgical resection remains the cornerstone of curative treatment for solid tumors. However, the inability to precisely visualize tumor margins intraoperatively and monitor therapeutic responses in real-time poses significant clinical challenges. Through rational molecular engineering strategy, we propose a novel class of tandem-locked, dual-activatable NIR-II fluorescent probes (HY-1-NO₂ to HY-4-NO₂) engineered for simultaneous response to NTR and microenvironmental viscosity, two biomarkers strongly associated with tumor malignancy and treatment response. Among all of the designed probes, HY-2-NO₂ demonstrates robust NIR-II emission at 910 nm with a 20-fold enhancement in fluorescence upon activation. This dual-key mechanism ensures high specificity and minimal background, enabling accurate intraoperative delineation of tumor margins with precision down to 0.2 mm. Furthermore, HY-2-NO₂ facilitates real-time evaluation of the paclitaxel-induced therapeutic response, with fluorescence intensity positively correlating with tumor suppression. The probe also successfully distinguishes tumor from normal tissues in clinical specimens, demonstrating strong translational potential. Thus, this study provides an integrated theranostic platform that combines real-time surgical navigation with functional monitoring of treatment efficacy, addressing critical gaps in precision oncology.