The construction of efficient enzyme mimetics for the hydrolysis of peptide bonds in proteins is challenging due to the high stability of peptide bonds and the importance of proteases in biology and industry. Metal-organic frameworks (MOFs) consisting of infinite crystalline lattices with metal clusters and organic linkers may provide opportunities for protease mimic which has remained unknown. Herein, we report that Cu2(C9H3O6)4/3 MOF (which is well known as HKUST-1 and denoted as Cu-MOF here), possesses an intrinsic enzyme mimicking activity similar to that found in natural trypsin to bovine serum albumin (BSA) and casein. The Michaelis constant (Km) of Cu-MOF is about 26,000-fold smaller than that of free trypsin indicating a much higher affinity of BSA for Cu-MOF surface. Cu-MOF also exhibited significantly higher catalytic efficiency than homogeneous artificial metalloprotease Cu(II) complexes and could be reused for ten times without losing in its activity. Moreover, Cu-MOF was successfully used to simulate trypsinization in cell culture since it dissociated cells in culture even without EDTA.

Though metal-organic frameworks (MOFs) have inspired potential applications in biomedicine, cytotoxicity studies of MOFs have been relatively rare. Here we demonstrate for the first time that an easily available MOF, Fe-MIL-101, possesses intrinsic activity against human SKOV3 ovarian cancer cells and suppress the proliferation of SKOV3 cells (IC50 = 23.6 μg mL−1) and normal mouse embryonic fibroblasts (BABL-3T3, IC50 = 78.3 μg mL−1) cells. It was more effective against SKOV3 cells than typical anticancer drugs such as artesunate (ART, IC50 = 96.9 μg mL−1) and oxaliplatin (OXA, IC50 = 64.4 μg mL−1), but had less effect on normal BABL-3T3 cells compared with ART (IC50 = 36.6 μg mL−1) and OXA (IC50 = 13.8 μg mL−1). Fe-MIL-101 induced apoptosis of human umbilical vein endothelial cells (HUVECs) via G0/G1 cell cycle arrest and decreased the mitochondrial membrane potential in HUVECs and induced apoptosis. Furthermore, Fe-MIL-101 exhibited stronger antiangiogenic effects in HUVEC cells than antiangiogenic inhibitor (SU5416) via downregulation the expression of MMP-2/9. Our results reveal a new role of Fe-MIL-101 as a novel, non-toxic anti-angiogenic agent that restricted ovarian tumour growth. These findings could open a new avenue of using MOFs as potential therapeutics in angiogenesis-dependent diseases, including ovarian cancer.

Solar-driven photocatalytic H2O2 production with water and O2 is an environmentally friendly process for producing H2O2, an important chemical. Compared with traditional photocatalysts, covalent organic frameworks (COFs) have received extensive...

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Photodynamic therapy (PDT) using two-photon near-infrared light excitation is a very effective way to avoid the use of shortwavelength ultraviolet or visible light which cannot efficiently penetrate into the biological tissues and is harmful to the healthy cells. Herein, a series of cyclometalated Ir(III) complexes with a structurally simple diimine ligand were designed and the synthetic route and preparation procedure were optimized, so that the complexes could be obtained in apparently higher yield, productivity, and efficiency in comparison to the traditional methods. Their ground state and excited singlet and triplet state properties were studied by spectroscopy and quantum chemistry theoretical calculations to investigate the effect of substituent groups on the photophysical properties of the complexes. The Ir(III) complexes, especially Ir1 and Ir3, showed very low dark toxicities and high phototoxicities under both one-photon and twophoton excitation, indicating their great potential as PDT agents. They were also found to be highly sensitive two-photon mitochondria dyes.