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

Abstract

Fluorescent probes in the second near-infrared window (NIR-II) allowh igh-resolution bioimaging with deep-tissue penetration. However,e xisting NIR-II materials often have poor signal-to-background ratios because of the lacko ft arget specificity.H erein, an activatable NIR-II nanoprobe for visualizing colorectal cancers was devised. This designed probe displays H 2 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 2 S-rich colon cancer cells,a ccurate 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.

H2S-activatable near-infrared afterglow luminescent probes for sensitive molecular imaging in vivo

“…Such activatable afterglow probes with large turn-on ratio and ultrafast reaction kinetics could facilitate sensitive and real-time detection of H 2 S in vitro and in vivo. H 2 S is recognized as the third signaling gasotransmitter, participating in many essential physiological and pathological processes [36][37][38][39] . Throughout the past few years, many colorimetric and fluorescent probes have been developed for H 2 S measurement [52][53][54][55][56][57] .…”

“…Hydrogen sulfide (H 2 S) is a highly reactive endogenous signaling molecule, playing a critical role in diverse physiological functions [33][34][35] . Aberrant concentration and tissue distribution of H 2 S are associated with many diseases (e.g., liver inflammation, hypertension, diabetes, and cancers) [36][37][38][39] . Therefore, precise spatiotemporal detection of H 2 S in living subjects is essential to the study of the biological functions and accurate diagnosis of H 2 Srelated diseases.…”

Recent advances in theranostic agents based on natural products for photodynamic and sonodynamic therapy

“…However, the compounds with NIR-II property are very limited, and all of them are artificially synthetic. 80,81 The theranostic agents based on natural products with NIR-II have not appeared yet until now, which should be noted in future. Alternatively, researchers also use the twophoton treatment to achieve a deeper depth PDT, but the two-photon therapy is still in the basic research stage because of a high demand of materials and low two-photon efficiency.…”

Surface Plasmon Resonance–Enhanced Photoacoustic Imaging and Photothermal Therapy of Endogenous H2S‐Triggered Au@Cu2O

“…In colon cancer, one of the specific physiological features is the highly expressed endogenous hydrogen sulfide (H 2 S) . Using endogenous H 2 S to trigger the photoacoustic imaging and photothermal therapy function of smart theranostics agents can effectively improve the diagnosis and treatment of colon cancer . For instance, Zhao and co‐workers developed an H 2 S‐triggered smart theranostics agent for NIR‐II fluorescence imaging–guided photothermal therapy .…”