A novel NIR-II nanoprobe for precision imaging of micro-meter sized tumor metastases of multi-organs and skin flap

Near-infrared window II (NIR-II, 1000 - 1700 nm) imaging shows high promise for medical applications. Novel NIR-II dyes are the driving force to realize and broaden the biomedical applications of this newly rising imaging technique. Herein, we designed a novel small molecular NIR-II dye IT-TQT using a new strategy and further loaded the dye into DSPE-PEG2000 to obtain IT-TQT nanoparticles (NPs) for bioimaging. Specifically, IT-TQT was integrated a novel component 6,7-di(thiophen-2-yl)- [1,2,5] thiadiazolo[3,4-g] quinoxaline (TQT) as electron acceptor and the indole group widely presented in pharmaceuticals as a novel electron donor. Taking advantage of the excellent photophysical properties of IT-TQT nanoprobe (diameter: 11.2 nm; maximum emission: 1015 nm), IT-TQT NPs clearly delineated tumors in subcutaneous mice models and realized the detection of even micro-meter (down to 90 mu m) ultrasmall tumors presented in multiple organs in living tumor metastases mice models. Furthermore, the vasculatures as small as 63.5 mu m in diameter were also identified in mice blood vessel imaging using IT-TQT NPs. Lastly, the survival area of the small animal mice and large animal porcine skin flap were successfully visualized by IT-TQT NPs. Overall, IT-TQT nanoprobe has high potential for broad biomedical applications and clinical translation.

Automated summary

The IT-TQT nanoprobe, developed using novel NIR-II dyes, effectively delineates tumors and blood vessels in various models, demonstrating broad potential for biomedical applications.