Imaging of Colorectal Cancers Using Activatable Nanoprobes with Second Near‐Infrared Window Emission

Abstract

Fluorescent probes in the second near-infrared window (NIR-II) allow high-resolution bioimaging with deep-tissue penetration. However, existing NIR-II materials often have poor signal-to-background ratios because of the lack of target specificity. Herein, an activatable NIR-II nanoprobe for visualizing colorectal cancers was devised. This designed probe displays H S-activated ratiometric fluorescence and light-up NIR-II emission at 900-1300 nm. By using this activatable and target specific probe for deep-tissue imaging of H S-rich colon cancer cells, accurate identification of colorectal tumors in animal models were performed. It is anticipated that the development of activatable NIR-II probes will find widespread applications in biological and clinical systems.

Organic Semiconducting Agents for Deep‐Tissue Molecular Imaging: Second Near‐Infrared Fluorescence, Self‐Luminescence, and Photoacoustics

“…Second, new approaches toward self‐luminescence in addition to ultralong phosphorescence and bio/chemiluminescence are highly wanted to improve the performance of self‐luminescence imaging including increased half‐life time and redshifted emission wavelength (from NIR‐I to NIR‐II). Third, there are a very few NIR‐II fluorescent/PA activatable probes, which are mainly caused by the difficulty in chemical modification of current organic semiconducting agents. With the emergence of new NIR‐II emitting and absorbing dyes, it is envisioned that more and more NIR‐II fluorescent/PA activatable probes will be developed to fully unlock the potential of NIR‐II optical imaging in medicine, particularly early diagnosis.…”

PITTCON 2019 Award Winners

“…Fan's current research is based on the development of nucleic acid tools for biomolecular sensing and live‐cell imaging. In Communications in Angewandte Chemie he has reported on live‐cell imaging of native RNA transcripts and near‐infrared imaging of colorectal cancers using activatable nanoprobes . Fan is a member of the Editorial Advisory Boards of ChemBioChem and ChemNanoMat .…”

Hexaarylbutadiene: A Versatile Scaffold with Tunable Redox Properties towards Organic Near‐Infrared Electrochromic Material

“…Recently, H 2 S was revealed to be the third gasotransmitter in biology, and its in vivo concentration and localization can be used to diagnose many diseases such as liver cancer . Dication 1 a 2+ was found to react efficiently with H 2 S over endogenous reducing agents (e. g., glutathione, L ‐cysteine and vitamin C) in cells to give 1 a .…”

“…Recently, H 2 S was revealed to be the third gasotransmitter in biology, and its in vivo concentration and localization can be used to diagnose many diseases such as liver cancer. [17][18][19] Dication 1 a 2 + was found to react efficiently with H 2 S over endogenous reducing agents (e. g., glutathione, L-cysteine and vitamin C) in cells to give 1 a. The large difference in the absorption spectra between 1 a 2 + and 1 a can be used for the OFF/ON switching mechanism of detection, and the activatable probe for non-invasive and real-time detection of H 2 S was successfully constructed based on the EM of 1 a/1 a 2 + .…”