Carbon dots (CDs) have significant potential for use in various fields including biomedicine, bioimaging, and optoelectronics. However, inefficient excitation and emission of CDs in both near-infrared (NIR-I and NIR-II) windows remains an issue. Solving this problem would yield significant improvement in the tissue-penetration depth for in vivo bioimaging with CDs. Here, an NIR absorption band and enhanced NIR fluorescence are both realized through the surface engineering of CDs, exploiting electron-acceptor groups, namely molecules or polymers rich in sulfoxide/carbonyl groups. These groups, which are bound to the outer layers and the edges of the CDs, influence the optical bandgap and promote electron transitions under NIR excitation. NIR-imaging information encryption and in vivo NIR fluorescence imaging of the stomach of a living mouse using CDs modified with poly(vinylpyrrolidone) in aqueous solution are demonstrated. In addition, excitation by a 1400 nm femtosecond laser yields simultaneous two-photon-induced NIR emission and three-photon-induced red emission of CDs in dimethyl sulfoxide. This study represents the realization of both NIR-I excitation and emission as well as two-photon- and three-photon-induced fluorescence of CDs excited in an NIR-II window, and provides a rational design approach for construction and clinical applications of CD-based NIR imaging agents.

Numerous studies have shown that berberine and its derivatives demonstrate important anti-tumor effects. However, the specific underlying mechanism remains unclear. Therefore, based on systems pharmacology, this review summarizes the information available on the anti-tumor effects and mechanism of berberine and its derivatives. The action and potential mechanism of action of berberine and its derivatives when used in the treatment of complex cancers are systematically examined at the molecular, cellular, and organismic levels. It is concluded that, with further in-depth investigations on their toxicity and efficacy, berberine and its derivatives have the potential for use as drugs in cancer therapy, offering improved clinical efficacy and safety.

Both a near‐infrared (NIR) absorption band and enhanced NIR fluorescence are realized by Songnan Qu, Andrey L. Rogach, and co‐workers, in article number https://doi.org/10.1002/adma.201705913, through surface engineering of carbon dots, exploiting electron‐acceptor groups, namely molecules or polymers rich in sulfoxide/carbonyl groups. Twophoton‐induced NIR emission and three‐photon‐induced red emission are simultaneously observed for carbon dots in dimethyl sulfoxide under excitation of a 1400 nm femtosecond pulse laser in the NIR‐II window.