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Ferroptosis is an iron-dependent, non-apoptotic form of programmed cell death driven by excessive lipid peroxidation (LPO). Mounting evidence suggests that the unique modality of cell death is involved in the development and progression of several diseases including cancer, cardiovascular diseases (CVDs), neurodegenerative disorders

Mitochondrial proteins, most of which are encoded in the nucleus and the rest of which are regulated by the mitochondrial genome, play pivotal roles in essential cellular functions. However, fluorescent probes that can be used for monitoring mitochondrial proteins have not yet been widely developed, thereby severely limiting the exploration of the functions of proteins in mitochondria. Towards this end, here we propose a near-infrared (NIR) fluorescence probe MPP to effectively illuminate the dynamic changes in mitochondrial proteins in live cells under oxidative stress, with excellent temporal and spatial resolution. Of particular importance, MPP extends the study of the pharmacology involved in apoptosis induced by anti-cancer drugs (hydroxycamptothecin (HCPT), epirubicin (Epi) and cyclophosphamide (CPA)) for the first time. Furthermore, employing a protein-activatable strategy, this probe could serve as an excellent phototherapeutic agent in photodynamic therapy (PDT). Finally, in vivo experiments suggest that this versatile probe can be used to image tumors in HeLa tumor-bearing mice for 24 h, which demonstrates that our probe could play a dual role as a robust phototherapeutic and imaging agent.

Bi2O2CO3 clusters made up of ultrathin nanosheets with predominated {001} facets were facilely synthesized via a template-free hydrothermal strategy at a mild temperature of 60 °C. Na2CO3 dosage and reaction temperature are confirmed to be key parameters to obtain the hydrolysis product of (Bi2O2)2+ from bismuth nitrate and provide a suitable microenvironment for the assembly of nanosheets. The sample exhibits obviously improved photocatalytic activity for the degradation and mineralization of Rhodamine B compared with thicker Bi2O2CO3 plates of less exposed {001} planes, with the reaction rate constant k enhanced by 3.4 fold. Photoluminescence and electrochemical impedance results confirm that the {001} facets are reactive and favorable for the separation and migration of photogenerated carriers, which primarily account for the superior photocatalytic behavior of the Bi2O2CO3 clusters. In addition, the enhanced specific surface area should also contribute to the improved photocatalytic activity. Based on the band edge positions of Bi2O2CO3 and the redox potentials of detected oxidative species, a possible migration mechanism of photogenerated e−/h+ pairs on the surface of Bi2O2CO3 is proposed. This work provides some new insight into the rational design and synthesis of facet-dependent semiconductor photocatalyst under mild conditions.

Flower shaped WO3 architectures weaved up of ultrathin nanorods with oriented {001} facets were successfully prepared via a facile ethanol/water solvothermal strategy, at a low temperature of 100 °C for 4 h. Characterizations of phase, morphology, microstructure, optical absorption, BET surface area, photoluminescence, photoelectrochemical properties and photocatalytic behavior were systematically explored. The volume ratio of ethanol and water was confirmed to be a key parameter in regulating the morphology and microstructure of WO3 by tuning the dielectric properties of the mixed solvent. The {001} faceted WO3 structures exhibit improved photocatalytic activity for the degradation of methyl orange with the reaction rate constant k enhanced by 2.1 fold, compared to the hydrothermal counterpart assembled by thick, individual WO3 nanorods. The active {001} facets with faster charge migration and enhanced surface area with more adsorption sites account for the excellent photocatalytic behavior. In addition, the active species in the photocatalytic reaction were investigated in detail, using terephthalic acid capture, ESR and radical scavengers. Combining the band edge positions of WO3 and the redox potentials of the active species, a possible migration mechanism of photogenerated e−/h+ pairs on the surface of WO3 is proposed. This work provides some new insights into the rational design and synthesis of facet-dependent 3D semiconductor photocatalysts.