Sub‑5 nm Ultrasmall Metal–Organic Framework Nanocrystals for Highly Efficient Electrochemical Energy Storage

Synthesis of ultrasmall metal–organic framework (MOF) nanoparticles has been widely recognized as a promising route to greatly enhance their properties but remains a considerable challenge. Herein, we report one facile and effective spatially confined thermal pulverization strategy to successfully transform bulk Co-MOF particles into sub-5 nm nanocrystals encapsulated within N-doped carbon/graphene (NC/G) by using conducting polymer coated Co-MOFs/graphene oxide as precursors. This strategy involves a feasible mechanism: calcination of Co-MOFs at proper temperature in air induces the partial thermal collapse/distortion of the framework, while the uniform coating of a conducting polymer can significantly improve the decomposition temperature and maintain the component stability of Co-MOFs, thus leading to the pulverization of bulk Co-MOF particles into ultrasmall nanocrystals without oxidation. The pulverization of Co-MOFs significantly increases the contact area between Co-MOFs with electrolyte and shortens the electron and ion transport pathway. Therefore, the sub-5 nm ultrasmall MOF nanocrystals-based composites deliver an ultrahigh reversible capacity (1301 mAh g^–1 at 0.1 A g^–1), extraordinary rate performance (494 mAh g^–1 at 40 A g^–1), and outstanding cycling stability (98.6% capacity retention at 10 A g^–1 after 2000 cycles), which is the best performance achieved in all reported MOF-based anodes for lithium-ion batteries

Data_Sheet_1_A soybean sodium/hydrogen exchanger GmNHX6 confers plant alkaline salt tolerance by regulating Na+/K+ homeostasis.PDF

Alkaline soil has a high pH due to carbonate salts and usually causes more detrimental effects on crop growth than saline soil. Sodium hydrogen exchangers (NHXs) are pivotal regulators of cellular Na+/K+ and pH homeostasis, which is essential for salt tolerance; however, their role in alkaline salt tolerance is largely unknown. Therefore, in this study, we investigated the function of a soybean NHX gene, GmNHX6, in plant response to alkaline salt stress. GmNHX6 encodes a Golgi-localized sodium/hydrogen exchanger, and its transcript abundance is more upregulated in alkaline salt tolerant soybean variety in response to NaHCO3 stress. Ectopic expression of GmNHX6 in Arabidopsis enhanced alkaline salt tolerance by maintaining high K+ content and low Na+/K+ ratio. Overexpression of GmNHX6 also improved soybean tolerance to alkaline salt stress. A single nucleotide polymorphism in the promoter region of NHX6 is associated with the alkaline salt tolerance in soybean germplasm. A superior promoter of GmNHX6 was isolated from an alkaline salt tolerant soybean variety, which showed stronger activity than the promoter from an alkaline salt sensitive soybean variety in response to alkali stress, by luciferase transient expression assays. Our results suggested soybean NHX6 gene plays an important role in plant tolerance to alkaline salt stress.</p

Ultrasound Triggered Conversion of Porphyrin/Camptothecin-Fluoroxyuridine Triad Microbubbles into Nanoparticles Overcomes Multidrug Resistance in Colorectal Cancer

Multidrug resistance remains one of the main obstacles to efficient chemotherapy of colorectal cancer. Herein, an efficient combination therapeutic strategy is proposed based on porphyrin/camptothecin-floxuridine triad microbubbles (PCF-MBs) with high drug loading contents, which own highly stable co-delivery drug combinations and no premature release. The triad PCF-MBs can act not only as a contrast agent for ultrasound (US)/fluorescence bimodal imaging but also a multimodal therapeutic agent for synergistic chemo-photodynamic combination therapy. Upon local ultrasound exposure under the guidance of ultrasound imaging, <i>in situ</i> conversion of PCF-MBs into porphyrin/camptothecin-floxuridine nanoparticles (PCF-NPs) leads to high accumulation of chemo-drugs and photosensitizer in tumors due to the induced high permeability of the capillary wall and cell membrane temporarily <i>via</i> sonoporation effect, greatly reducing the risk of systemic exposure. Most importantly, it was found that the PCF-MB-mediated photodynamic therapy could significantly reduce the expression of adenosine-triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG₂), which is responsible for the drug resistance in chemotherapy, resulting in a prominent intracellular camptothecin increase. <i>In vivo</i> experiments revealed that the PCF-MBs in combination with ultrasound and laser irradiation could achieve a 90% tumor inhibition rate of HT-29 cancer with no recurrence. Therefore, such triad PCF-MB-based combination therapeutic strategy shows great promise for overcoming drug resistance of colorectal cancer and other cancers