A new fluorescent imaging probe indocyanine green-VC (ICG-VC) in the second near-infrared window (NIR-II) was fabricated based on the urokinase-type plasminogen activator receptor (uPAR) targeted polypeptide VC (VSNKYFSNIHWGC). The relative quantum yield (phi(F))was 0.34 %. The tail of its fluorescence emission wavelength exceeded 1000 nm with excellent photostability. In vitro cell analysis, MTT results indicated the high biocompatibility of ICG-VC with U87MG cells. ICG-VC showed good photothermal conversion behavior and photothermal stability.In vivo NIR-II fluorescence imaging, ICG-VC exhibited high spatiotemporal resolution in the lymphatic vessels with a high resolution of 717 mu m and signal-to-noise ratio of 4.36, and displayed an excellent U87MG tumor uptake within 4 h, which reached the maximum at 8 h with a signal-to-noise ratio of 5.32.
基金:
Hubei Province Key Laboratory of Molecular Imaging [2020fzyx011]