Incorporation of multiwalled carbon nanotubes (CNTs) into a metal–organic framework (TCPP-U1) was able to maintain the crystal structure and morphology of the original TCPP-U1 while enhancing the hydrolytic stability. In addition, CNTs@TCPP-U1 had a photocatalytic effect on the degradation of tetracycline hydrochloride in aqueous solution.

Owing to their highly predictable porous structures, facile synthesis, and the presence of functional open metal sites, metal–organic frameworks (MOFs) are extensively employed in various fields, including energy storage, catalysis, adsorption, and separation. Nevertheless, the limited hydrolytic stability exhibited by numerous MOFs poses a significant challenge to their practical application. In the present study, we present the synthesis and characterization of a uranyl organic framework (TCPP-U1) with a highly porous structure, which is constructed by assembling cobalt, uranyl, and the porphyrin ligand 5,10,15,20-tetra(4-carboxyphenyl)porphyrin (TCPP). However, TCPP-U1 demonstrates poor hydrolytic stability when exposed to water (the structure can be destroyed even after 2 min of exposure to water), greatly impeding its potential applications that would benefit from its high surface area. To address this limitation, we developed a hybrid composite by incorporating acid-treated multi-walled carbon nanotubes (CNTs) into the TCPP-U1 framework via a solvothermal method designated as CNTs@TCPP-U1. Remarkably, the obtained CNTs@TCPP-U1 composite possesses an identical crystal structure and morphology to the original TCPP-U1 yet exhibits significant enhancements in hydrolytic stability (the structure remains stable even after 3 days of immersion in water). Furthermore, CNTs@TCPP-U1 demonstrates a significant photocatalytic effect on the degradation of tetracycline hydrochloride in aqueous solutions. The reaction rate constant (k) for the pseudo-first-order kinetic model is 0.0059 min⁻¹. Our findings present a novel perspective for enhancing the stability and expanding the performance of MOFs materials.

A newly synthesized azo dye ligand and its Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) complexes require a range of techniques, including elemental analyses and spectroscopic studies. Nitrogen of the azo group and one oxygen of the carbonyl group coordinate the azo ligand to the metal ions, acting as a neutral bidentate ligand, according to the inferred IR spectra. The molar conductance data indicated that all the complexes were electrolytes. Octahedral geometry was suggested for the complexes being studied. The proposed structural equations for the complexes were, in general, expressed as [M(L)Cl₂(H₂O)₂]·Cr(III), x = 1, n = 0; Cd(II), x = n = 0; Zn(II), x = 0, n = 1, and [M(L)(Cl)(H₂O)₃] Clx·nH₂O Mn(II), Co(II), Ni(II), and Cu(II), x = 1; Clx [M = Fe(III), x = 2].

A novel azo dye ligand was created by diazotizing 4-aminoantipyrine and then coupling it with 2-aminophenol as part of a methodical investigation of physiologically active compounds, 4-aminoantipyrine. The novel complexes containing Cr(III), Fe(III), Mn(II), Co(II), Ni(II), Zn(II), Cu(II), and Cd(II) were created from the target ligand (L). The structures of the ligand and metal complexes were verified by elemental analyses, thermogravimetric analysis–difference thermogravimetry (TGA-DTG), conductivity measurements, infrared (IR), UV–Vis, ¹H-nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and mass spectrometry. Using the Gaussian 09 tool, the density functional theory (DFT)/B3LYP method was utilized to compute the energy gaps and other important theoretical features. Also, the newly synthesized azo dye ligand, in comparison with metal complexes, was screened for its antimicrobial activity. The crystal structures of Staphylococcus aureus and Bacillus subtilis as gram-positive bacteria, Salmonella sp. and Escherichia coli as gram-negative bacteria, and fungal (Aspergillus fumigatus and Candida albicans) species were compared with the produced azo dye and its metal complexes via molecular docking. Most of the complexes exhibited greater antimicrobial activities against these organisms than did the original azo dye ligand.

The gold(I)N-heterocyclic-carbene complexes containing 6-mercaptopurine derivatives revealed promising in vitro cytotoxicity against selected human cancer cells. The effects of the complexes on the production of pro-inflammatory cytokine TNF-α and the activation of NF-κB or PPARγ are negligible. Cellular effects of complexes were evaluated on A2780 cells, including cell cycle modification, induction of cell death, mitochondrial membrane potential, and ROS. The proteomic analysis revealed the effects of the complexes on the proteome of A2780 cells.

A series of eight N-heterocyclic carbenes (NHC) gold(I) complexes, involving 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (iPr) ligand in combination with 6-mercaptopurine derivatives (HL_1–8), has been prepared and thoroughly characterized, including elemental analysis, mass spectrometry, infrared and multinuclear NMR spectroscopy, and single crystal X-ray analysis. The complexes, showing general composition of [Au (iPr)(L_n)] 1–8, were evaluated for their in vitro cytotoxicity against four human cancer cell lines including A2780 (ovarian) and A2780R (ovarian Cisplatin resistant), PC3 (prostate) and MCF-7 (breast), and normal human MRC-5 cells (lung fibroblasts). The complexes revealed significant cytotoxicity, with the best IC₅₀ values ≈ 3.4–6.4 μM against A2780 and reasonable selectivity. Cellular effects of the selected complexes on the A2780 cells were evaluated using various flow cytometry assays. Complexes 1, 3, and 4 showed a strong pro-apoptotic effect and a strong effect on the loss of mitochondrial membrane potential. These findings indicate that their major mechanism of action is based on the collapse of the mitochondrial metabolism and activation of the intrinsic signaling pathway of apoptosis, consequently resulting in cell death. The complexes 1–8 revealed only negligible effect on the production of inflammatory-related cytokine (TNF-α), as well as the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) or peroxisome proliferator-activated receptor gamma (PPARγ). Moreover, the shotgun proteomic analysis was performed, and the obtained results suggest that the mechanism of action of complexes 1, 3, and 4 differs somewhat from that of Auranofin.