An efficient natural product-derived theranostic fluorescent probe for carboxylesterase bioimaging and activatable therapy of colon tumors.

Natural products have demonstrated significant potential in the treatment of many diseases. However, designing a diagnostic and therapeutic integrated system derived from natural products still poses significant challenges. This work proposes a drug delivery strategy based on natural products, which involves linking natural products to reactive moieties of tumor markers. Herein, a novel fluorescent probe (S-CES) for carboxylesterase 2 (CES2) imaging and therapy of colon tumor has been formulated and put to successful use both in vitro and in vivo. The probe was designed by combining trimethylacetate ester group with scopoletin, which itself can serve both as a tracer and drug in the treatment of colon tumor. S-CES exhibits high selectivity and sensitivity, low cytotoxicity, and excellent bio-compatibility, enabling the monitoring of endogenous CES2 activity in living cells. Moreover, it demonstrates favorable targeting specificity toward colon tumors. Consequently, this study offers a promising and robust strategy for the treatment of other diseases, while also augmenting the potential of natural products to exert a more significant role in clinical practice.