α_vβ₃ integrin-targeted IR-820 dye-based small molecule probe for fluorescence imaging of tumor

Owing to its advantages of high sensitivity, high specificity, and real-time detection capabilities, fluorescence molecular imaging techniques, such as near-infrared (NIR) fluorescence imaging, have been used to real-time intraoperative navigation in oncological surgery. Despite a variety of NIR fluorescent probes have been developed for tumor detection in biological field, just limited amount of these probes including the 5-aminolevulinic acid, fluoresceine, methylene blue and pafolacianine were approved by FDA for clinical use. And only pafolacianine has the tumor target property. Herein, we developed a near-infrared fluorescent probe IR-820-cRGD for in vivo tumor imaging. This probe integrates the near-infrared dye IR-820 with a cyclic peptide cRGD that can bind to the integrin α_vβ₃ receptor overexpressed on the surface of tumor cells, thus enabling the probe specifically accumulate at the tumor site. The results suggested that both the MDA-MB-231 cell line and tumor regions of nude mouse tumor models exhibited significantly higher fluorescence intensity compared to the normal cells or tissues. This demonstrates the probe's capability for precise tumor localization with low background signal, offering potential for early tumor diagnosis and therapeutic applications such as fluorescence-guided surgery.