liumeng030620

In this work, for the first time, we constructed a novel multi-nanozymes cooperative platform to mimic intracellular antioxidant enzyme-based defense system. V₂O₅ nanowire served as a glutathione peroxidase (GPx) mimic while MnO₂ nanoparticle was used to mimic superoxide dismutase (SOD) and catalase (CAT). Dopamine was used as a linker to achieve the assembling of the nanomaterials. The obtained V₂O₅@pDA@MnO₂ nanocomposite could serve as one multi-nanozyme model to mimic intracellular antioxidant enzyme-based defense procedure in which, for example SOD, CAT, and GPx co-participate. In addition, through assembling with dopamine, the hybrid nanocomposites provided synergistic antioxidative effect. Importantly, both in vitro and in vivo experiments demonstrated that our biocompatible system exhibited excellent intracellular reactive oxygen species (ROS) removal ability to protect cell components against oxidative stress, showing its potential application in inflammation therapy.

Artificial enzyme complexes: A multi-nanozyme cooperative platform was constructed to mimic an intracellular antioxidant enzyme-based defense system and protect cells against oxidative stress (see picture). This development holds great promise for potential applications in cancer and inflammation therapy.

Despite the growing interest in iron catalysis and hydroamination reactions, iron-catalyzed hydroamination of unprotected primary aliphatic amines and unactivated alkenes has not been reported to date. Herein, a novel well-defined four-coordinate β-diketiminatoiron(II) alkyl complex is shown to be an excellent precatalyst for the highly selective cyclohydroamination of primary aliphatic alkenylamines at mild temperatures (70–90 °C). Both empirical kinetic analyses and the reactivity of an isolated iron(II) amidoalkene dimer, [LFe(NHCH₂CPh₂CH₂CHCH₂)]₂ favor a stepwise σ-insertive mechanism that entails migratory insertion of the pendant alkene into an iron–amido bond associated with a rate-determining aminolysis step.

Iron horseshoe: A well-defined four-coordinate β-diketiminatoiron(II) alkyl complex is a precatalyst for the highly selective cyclohydroamination of primary aliphatic alkenylamines at mild temperatures. Its mechanism is also elucidated.