Dual‐Locked Fluorescent Probes Activated by Aminopeptidase N and the Tumor Redox Environment for High‐Precision Imaging of Tumor Boundaries

Clear delineation of tumor margins is essential for accurate resection and decreased recurrence rate in the clinic. Fluorescence imaging is emerging as a promising alternative to traditional visual inspection by surgeons for intraoperative imaging. However, traditional probes lack accuracy in tumor diagnosis, making it difficult to depict tumor boundaries accurately. Herein, we proposed an offensive and defensive integration (ODI) strategy based on the “attack systems (invasive peptidase) and defense systems (reductive microenvironment)” of multi‐dimensional tumor characteristics to design activatable fluorescent probes for imaging tumor boundaries precisely. Screened out from a series of ODI strategy‐based probes, ANQ performed better than traditional probes based on tumor unilateral correlation by distinguishing between tumor cells and normal cells and minimizing false‐positive signals from living metabolic organs. To further improve the signal‐to‐background ratio in vivo, derivatized FANQ, was prepared and successfully applied to distinguish orthotopic hepatocellular carcinoma tissues from adjacent tissues in mice models and clinical samples. This work highlights an innovative strategy to develop activatable probes for rapid diagnosis of tumors and high‐precision imaging of tumor boundaries, providing more efficient tools for future clinical applications in intraoperative assisted resection. A series of offensive and defensive integration (ODI) strategy‐based fluorescent probes depending on the “attack and defense systems” required for the persistence of tumors is reported. FANQ was screened for tumor imaging, distinguishing between cancerous tissue and adjacent tissue with an obvious tumor boundary.