Real-time diagnosis of glioblastoma by sensing peroxynitrite with a highly selective and rapid-responding fluorescent probe

Glioblastoma is the most concealment malignant intracranial tumor due to tumor heterogeneity and obstruction of blood-brain barrier (BBB). Peroxynitrite (ONOO-) is an extremely strong oxidant, and a biomarker closely related to cancer. Real-time monitoring of the ONOO- levels in glioblastoma is important for the early diagnosis. Herein, we developed a novel enhanced fluorescent probe, named ZONQ, with superior rapid response and specific selectivity for ONOO-, even in the presence of ROS (Reactive oxygen species) and biological species. Due to its significant advantages, we were delighted to find that the probe ZONQ could also be used to image endogenous ONOO- in live cells, glioblastoma tissue, and transplanted tumor mice. In vitro 3D tumor sphere experiments and in vivo studies have demonstrated that the probe ZONQ has excellent tissue penetration and targeting capabilities in brain glioblastoma. Confocal and intravital imaging showed significant fluorescent signals even when incubated with low concentrations of probe ZONQ. In addition, ZONQ showed significant feasibility in the elemental analysis of the spanning BBB. Based on this evidence, this novel fluorescent probe showed promising potential for use in the clinical real-time diagnosis of glioblastoma.