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bioRxiv · 10.1101/2020.05.26.113316

An exploratory rehearsal on AIE dots assisted NIR-II fluorescence non-human primates imaging

Abstract

Superb reliability and biocompatibility equip aggregation-induced emission (AIE) dots with tremendous potential for fluorescence bioimaging. However, there is still a chronic lack of design instructions of excretable and bright AIE emitters. Here, we designed a kind of PEGylated AIE (OTPA-BBT) dots with strong absorption and extremely high NIR-II PLQY as 13.6%, and proposed the long-aliphatic-chain design blueprint contributing to their excretion from animal body. Assisted by the OTPA-BBT dots with bright fluorescence beyond 1100 nm and even 1500 nm (NIR-IIb), large-depth cerebral vasculature (beyond 600 m) as well as real-time blood flowing were monitored through-thinned-skull, and noninvasive NIR-IIb imaging with rich high-spatial-frequency information gave a precise presentation of gastrointestinal tract in marmosets. Importantly, after intravenous or oral administration, the definite excretion of OTPA-BBT dots from the body was demonstrated, which showed an influential evidence of bio-safety.

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Feng, Z., Bai, S., Qi, J., Sun, C., Zhang, Y., Yu, X., Ni, H., Wu, D., Fan, X., Xue, D., Gong, J., Wei, P., He, M., Lam, J. W. Y., Li, X., Tang, B. Z., Gao, L., Qian, J.. 2020-05-27. An exploratory rehearsal on AIE dots assisted NIR-II fluorescence non-human primates imaging. https://doi.org/10.1101/2020.05.26.113316

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