The biological mode of action of artemisinin, a potent antimalarial, has long been controversial. Previously we established a yeast model addressing its mechanism of action and found mitochondria the key in executing artemisinin's action. Here we present data showing that artemisinin directly acts on mitochondria and it inhibits malaria in a similar way as yeast. Specifically, artemisinin and its homologues exhibit correlated activities against malaria and yeast, with the peroxide bridge playing a key role for their inhibitory action in both organisms. In addition, we showed that artemisinins are distributed to malarial mitochondria and directly impair their functions when isolated mitochondria were tested. In efforts to explore how the action specificity of artemisinin is achieved, we found strikingly rapid and dramatic reactive oxygen species (ROS) production is induced with artemisinin in isolated yeast and malarial but not mammalian mitochondria, and ROS scavengers can ameliorate the effects of artemisinin. Deoxyartemisinin, which lacks an endoperoxide bridge, has no effect on membrane potential or ROS production in malarial mitochondria. OZ209, a distantly related antimalarial endoperoxide, also causes ROS production and depolarization in isolated malarial mitochondria. Finally, interference of mitochondrial electron transport chain (ETC) can alter the sensitivity of the parasite towards artemisinin. Addition of iron chelator desferrioxamine drastically reduces ETC activity as well as mitigates artemisinin-induced ROS production. Taken together, our results indicate that mitochondrion is an important direct target, if not the sole one, in the antimalarial action of artemisinins. We suggest that fundamental differences among mitochondria from different species delineate the action specificity of this class of drugs, and differing from many other drugs, the action specificity of artemisinins originates from their activation mechanism.

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MXene combining high metal-like conductivity, high hydrophilicity, and abundant surface functional groups has been recognized as a class of versatile two-dimensional materials for many applications. However, the aggregation of MXene nanosheets from interlayer van der Waals force and hydrogen bonds represents a major problem that severely limits their practical use. Here, we report an aerogel structure of MOFs@ MXene, in which the in situ formed MOF particles can effectively prevent the accumulation of MXene, enabling a three-dimensional (3D) hierarchical porous conductive network to be composed with an ultralight feature. Subsequently, a 3D porous MXene aerogel threaded hollow CoS nanobox composite ((CoS NP@NHC)@MXene) derived from the MOFs@MXene aerogel precursor was synthesized, and the highly interconnected MXene network and hierarchical porous structure coupled with the ultrafine nanocrystallization of the electrochemically active phase of CoS yield the hybrid system with excellent electron and ion transport properties. Benefiting from the synergistic effect of the components, the (CoS NP@NHC)@MXene composite manifests outstanding electrochemistry properties as electrode materials for all of the lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), and potassium-ion batteries (PIBs). It demonstrated the excellent cycle stability and high capacities of 1145.9 mAh g −1 at 1 A g −1 after 800 cycles and 574.1 mAh g −1 at 5 A g −1 after 1000 cycles for LIBs, 420 mAh g −1 at 2 A g −1 after 650 cycles for SIBs, and 210 mAh g −1 at 2 A g −1 after 500 cycles for PIBs. First-principle calculations confirmed that the (CoS NP@NHC)@MXene hybrid could enhance the charge transfer reaction kinetics, particularly at the interface. More importantly, the excellent rate performance under high mass loading and the high volumetric energy and power density of the entire electrode represent the potential of (CoS NP@NHC) @MXene composites for applications to practical electrochemical energy storage devices. The synthesis method reported in this Article is versatile and can be easily extended to produce other porous MXene-aerogel-based materials for various applications.

Magnetoelectric multiferroics have received much attention in the past decade due to their interesting physics and promising multifunctional performance. For practical applications, simultaneous large ferroelectric polarization and strong magnetoelectric coupling are preferred. However, these two properties have not been found to be compatible in the single-phase multiferroic materials discovered as yet. Here, it is shown that superior multiferroic properties exist in the A-site ordered perovskite BiMn Cr O synthesized under high-pressure and high-temperature conditions. The compound experiences a ferroelectric phase transition ascribed to the 6s lone-pair effects of Bi at around 135 K, and a long-range antiferromagnetic order related to the Cr spins around 125 K, leading to the presence of a type-I multiferroic phase with huge electric polarization. On further cooling to 48 K, a type-II multiferroic phase induced by the special spin structure composed of both Mn- and Cr-sublattices emerges, accompanied by considerable magnetoelectric coupling. BiMn Cr O thus provides a rare example of joint multiferroicity, where two different types of multiferroic phases develop subsequently so that both large polarization and significant magnetoelectric effect are achieved in a single-phase multiferroic material.