posted on 2024-01-16, 22:33authored byHuihui Xu, Lishan Yuan, Qiankun Shi, Ye Tian, Fang Hu
Fluorescence imaging is a vital way to delineate the
tumor boundaries.
Here, we achieve a NIR-II aggregation-induced emission luminogen (AIEgen)
with a fluorescence quantum yield (QY) of 12.6% in water through straightforward
alkyl side chain modification. After loading of NIR-II AIEgen into
polystyrene (PS) nanospheres, the thermal deactivation pathway is
extremely limited, thereby concentrating absorption excitation on
fluorescence emission. The fluorescence intensity is further enhanced
by 5.4 times, the QY increases to 21.1%, and the NIR-II imaging signal
is accordingly enhanced by 8.7 times, surpassing conventional DSPE-PEG
carriers. The NIR-II@PS nanoprobe showcases superior resolution and
tissue penetration depth compared to indocyanine green (ICG) and short-range
near-infrared AIEgens. In vivo investigations underscore
its tumor-to-normal tissue ratio (3.9) at 24 h post intravenous injection,
enabling complete resection of ≤1 mm metastases under NIR-II
bioimaging guidance. Additionally, the PS carrier-nanoparticles exhibit
low toxicity in vivo, laying a promising foundation
for the future design of medical nanomaterials.