Search

To solve the oxygen dependence problem of photodynamic therapy (PDT), it is critical to explore photosensitizers that do not rely on O2 molecule to generate reactive oxygen species (ROS). Herein, a stable cationic metal‐organic cage [Pd6(RuLoz3)8](BF4)28 (MOC‐88) that possesses high +28 charges is designed. The cage‐confined positive microenvironment enables efficient generation of hydroxyl radicals and improved yield of the singlet oxygen under one‐/two‐photon excitation, showing excellent performance to concurrently enhance Type‐II and O2‐independent‐Type‐I PDT. Moreover, the effective ROS production and robust lipid peroxidation trigger a series of signaling pathways (inflammasome, cyclic guanosine monophosphate–adenosine monophosphate synthase stimulator of interferon genes, and NF‐κB) to evoke PANoptosis and ferroptosis in tumor cells, enabling MOC‐88 to simultaneously cause the loss of cell membrane integrity, release a series of inflammatory cytokines and damage‐associated molecular patterns, stimulate the maturation and antigen presentation ability of dendritic cells, and ultimately activate T‐cell‐dependent adaptive immunity in vivo to inhibit tumor growth. [ABSTRACT FROM AUTHOR]

A series of isostructural supramolecular cages with a rhombic dodecahedron shape have been assembled with distinct metal‐coordination lability (M8Pd6‐MOC‐16, M=Ru2+, Fe2+, Ni2+, Zn2+). The chirality transfer between metal centers generally imposes homochirality on individual cages to enable solvent‐dependent spontaneous resolution of Δ8/Λ8−M8Pd6 enantiomers; however, their distinguishable stereochemical dynamics manifests differential chiral phenomena governed by the cage stability following the order Ru8Pd6>Ni8Pd6>Fe8Pd6>Zn8Pd6. The highly labile Zn centers endow the Zn8Pd6 cage with conformational flexibility and deformation, enabling intrigue chiral‐Δ8/Λ8−Zn8Pd6 to meso‐Δ4Λ4−Zn8Pd6 transition induced by anions. The cage stabilization effect differs from inert Ru2+, metastable Fe2+/Ni2+, and labile Zn2+, resulting in different chiral‐guest induction. Strikingly, solvent‐mediated host–guest interactions have been revealed for Δ8/Λ8−(Ru/Ni/Fe)8Pd6 cages to discriminate the chiral recognition of the guests with opposite chirality. These results demonstrate a versatile procedure to control the stereochemistry of metal‐organic cages based on the dynamic metal centers, thus providing guidance to maneuver cage chirality at a supramolecular level by virtue of the solvent, anion, and guest to benefit practical applications. [ABSTRACT FROM AUTHOR]

A series of isostructural supramolecular cages with a rhombic dodecahedron shape have been assembled with distinct metal‐coordination lability (M8Pd6‐MOC‐16, M=Ru2+, Fe2+, Ni2+, Zn2+). The chirality transfer between metal centers generally imposes homochirality on individual cages to enable solvent‐dependent spontaneous resolution of Δ8/Λ8−M8Pd6 enantiomers; however, their distinguishable stereochemical dynamics manifests differential chiral phenomena governed by the cage stability following the order Ru8Pd6>Ni8Pd6>Fe8Pd6>Zn8Pd6. The highly labile Zn centers endow the Zn8Pd6 cage with conformational flexibility and deformation, enabling intrigue chiral‐Δ8/Λ8−Zn8Pd6 to meso‐Δ4Λ4−Zn8Pd6 transition induced by anions. The cage stabilization effect differs from inert Ru2+, metastable Fe2+/Ni2+, and labile Zn2+, resulting in different chiral‐guest induction. Strikingly, solvent‐mediated host–guest interactions have been revealed for Δ8/Λ8−(Ru/Ni/Fe)8Pd6 cages to discriminate the chiral recognition of the guests with opposite chirality. These results demonstrate a versatile procedure to control the stereochemistry of metal‐organic cages based on the dynamic metal centers, thus providing guidance to maneuver cage chirality at a supramolecular level by virtue of the solvent, anion, and guest to benefit practical applications. [ABSTRACT FROM AUTHOR]

Porous supramolecular assemblies constructed by noncovalent interactions are promising for adsorptive purification of methane because of their easy regeneration. However, the poor stability arising from the weak noncovalent interactions has obstructed their practical applications. Here, we report a robust and easily regenerated polyhedron‐based cationic framework assembled from a metal–organic square. This material exhibits a very low affinity for CH4 and N2, but captures other competing gases (e.g. C2H6, C3H8, and CO2) with a moderate affinity. These results underpin highly selective separation of a range of gas mixtures that are relevant to natural gas and industrial off‐gas. Dynamic breakthrough studies demonstrate its practical separation for C2H6/CH4, C3H8/CH4, CO2/N2, and CO2/CH4. Particularly, the separation time is ≈11 min g−1 for the C2H6/CH4 (15/85 v/v) mixture and ≈49 min g−1 for the C3H8/CH4 (15/85 v/v) mixture (under a flow of 2.0 mL min−1), respectively, enabling its capability for CH4 purification from light alkanes. [ABSTRACT FROM AUTHOR]

Porous supramolecular assemblies constructed by noncovalent interactions are promising for adsorptive purification of methane because of their easy regeneration. However, the poor stability arising from the weak noncovalent interactions has obstructed their practical applications. Here, we report a robust and easily regenerated polyhedron‐based cationic framework assembled from a metal–organic square. This material exhibits a very low affinity for CH4 and N2, but captures other competing gases (e.g. C2H6, C3H8, and CO2) with a moderate affinity. These results underpin highly selective separation of a range of gas mixtures that are relevant to natural gas and industrial off‐gas. Dynamic breakthrough studies demonstrate its practical separation for C2H6/CH4, C3H8/CH4, CO2/N2, and CO2/CH4. Particularly, the separation time is ≈11 min g−1 for the C2H6/CH4 (15/85 v/v) mixture and ≈49 min g−1 for the C3H8/CH4 (15/85 v/v) mixture (under a flow of 2.0 mL min−1), respectively, enabling its capability for CH4 purification from light alkanes. [ABSTRACT FROM AUTHOR]

The article titled "Cover Picture: Dynamic Stereochemistry of M8Pd6 Supramolecular Cages Based on Metal-Center Lability for Differential Chiral Induction, Resolution, and Recognition" explores the stereochemical properties of metal-organic cages (MOCs) and their potential applications in chiral induction, resolution, and recognition. The authors demonstrate how the dynamic stereochemistry of the cages is influenced by the coordination lability of the metal centers, and how these behaviors can be controlled through guest interactions. The article also includes research on other topics such as fluorescent materials, photocatalysis, and quorum sensing. [Extracted from the article]