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Peroxalate CL as an energy source to excite photosensitizers has attracted tremendous attention in photodynamic therapy (PDT). In this work, peroxyoxalate CPPO and hypocrellin B (HB)‐based nanoparticles (CBNPs) for ultrasound (US)‐enhanced self‐exciting PDT were designed and prepared. CBNPs showed an excellent therapeutic effect against cancer cells with the assistance of US. This US‐enhanced‐chemiluminescence system avoids the dependence on external light and provides an example for inspiring more effective and precise strategies for cancer treatment. [ABSTRACT FROM AUTHOR]

Hypocrellin B (HB) derived from naturally produced hypocrellins has attracted considerable attention in photodynamic therapy (PDT) because of its excellent photosensitive properties. However, the weak absorption within a "phototherapy window" (600–900 nm) and poor water solubility of HB have limited its clinical application. In this study, two HB derivatives (i. e., HE and HF) were designed and synthesized for the first time by introducing two different substituent groups into the HB structure. The obtained derivatives showed a broad absorption band covering the near‐infrared (NIR) region, NIR emission (peaked at 805 nm), and singlet oxygen quantum yields of 0.27/0.31. HE‐PEG‐NPs were also prepared using 2‐distearoyl‐sn‐glycero‐3‐phosphoethanolamine‐N‐[methoxy(polyethyleneglycol)‐2000] (DSPE‐mPEG2000) to achieve excellent dispersion in water and further explored their practical applications. HE‐PEG‐NPs not only retained their 1O2‐generating ability, but also exhibited a photothermal conversion efficiency of 25.9%. In vitro and in vivo therapeutic results revealed that the synergetic effect of HE‐PEG‐NPs on PDT and photothermal therapy (PTT) could achieve a good performance. Therefore, HE‐PEG‐NPs could be regarded as a promising phototheranostic agent. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs), a kind of phototheranostic agent with the capability of simultaneous bioimaging and phototherapy [i.e. photodynamic therapy (PDT) or photothermal therapy (PTT)], have received considerable attention because of their remarkable properties, including flexibility for surface modification, high biocompatibility, low toxicity and photo‐induced activity for malignant tumor cells. Among numerous carbon sources, it has been found that natural biomass are good candidates for the preparation of CD phototheranostic agents. In this study, pheophytin, a type of Mg‐free chlorophyll derivative and also a natural product with low toxicity, was used as a raw carbon source for the synthesis of CDs by using a microwave method. The obtained hydrophobic CDs exhibited a maximum near‐infrared (NIR) emission peak at approximately 680 nm, and high singlet oxygen (1O2) generation with a quantum yield of 0.62. The self‐assembled CDs from the as‐prepared CDs with DSPE‐mPEG2000 retained efficient 1O2 generation. The obtained carbon dot assembly was not only an efficient fluorescence (FL) imaging agent but also a smart PDT agent. Our studies indicated that the obtained hydrophilic CD assembly holds great potential as a new phototheranostic agent for cancer therapy. This work provides a new route for synthesis of CDs and proposes a readily available candidate for tumor treatment. [ABSTRACT FROM AUTHOR]

Fluorescence imaging is a promising tool for the visualization of biomolecules in living systems and there is great demand for new fluorescent dyes that absorb and emit in the near-infrared (NIR) region. Herein, we constructed three new fluorescent dyes ( NBC dyes) based on keto-benzo[ h]coumarin ( k-BC) and benzopyrilium salts. These dyes showed large Stokes shifts (>100 nm) and NIR emission (>800 nm). The relationship between the structures and optical properties of these dyes was further investigated by using density functional theory calculations at the B3LYP/6-3G level of theory. Fluorescence images indicated that the fabricated dyes exhibited good photostability and low cytotoxicity and, thus, have potential applications as imaging agents in living cells and animals. [ABSTRACT FROM AUTHOR]

Volvox-like Cd xZn1− xS solid solutions with a cubic zinc blend structure were synthesized through a template-free ethylene glycol process. Cd(Ac)2 ⋅2 H2O, Zn(Ac)2 ⋅2 H2O, and thiourea are used as the starting materials and dissolved in ethylene glycol. These reaction precursors and solvent not only contributed to control over the formation of the volvox-like spherical geometry, but also exerted vigorous domination for existence of cubic-phase Cd xZn1− xS nanostructures. As-prepared volvox-like Cd xZn1− xS nanospheres have a diameter of around 100 nm with extensional shells. These samples show excellent photocatalytic H2 evolution activity from water splitting under visible-light irradiation without any cocatalyst or scaffolding, owing to their tunable band gap, cubic zinc blend structure, and unique hierarchical porous structure with a high surface area (as high as 95.2 m2 g−1). [ABSTRACT FROM AUTHOR]