Mixed membrane matrices (MMMs) made up with Nafion and nanocrystals of zirconium metal-organic framework (MOF) UiO-66 or the analogous sulfonated SOH-UiO-66 were prepared by varying the filler loading and the size of the crystals. The combined effects of size and loading, together with the presence of sulfonic groups covalently linked to the MOFs, were studied with regard to the conductivity and mechanical properties of the obtained composite matrices. A large screening of membranes was preliminarily made and, on the most promising samples, an accurate conductivity study at different relative humidities and temperatures was also carried out. The results showed that membranes containing large crystals (200 nm average size) in low amounts (around 2%) displayed the best results in terms of proton conductivity values, reaching values by 30% higher than those of pure Nafion, while leaving the mechanical properties substantially unchanged. On the contrary, MMMs containing MOFs of small size (20 nm average size) did not show any conductivity improvements if compared to pure Nafion membranes. The effect of MOF sulfonation was negligible at low filler loading whereas it became important at loading values around 10%. Finally, membranes with a high filler loading (up to 60 wt %) of sulfonated UiO-66 showed a slight reduction of conductivity in comparison with membranes loaded at 20% of nonsulfonated ones.

A novel Schiff base [C20H23NO3], has been prepared and characterized using FT-IR, UV-vis, (1)H NMR spectroscopy, elemental analysis and X-ray crystallography. A copper (II) complex [Cu(C20H22NO3)2]·H2O has also been synthesized and characterized. The new ligand and complex thus obtained were investigated by their interaction with calf thymus DNA and BSA using electronic absorption spectroscopy, fluorescence spectroscopy, and thermal denaturation. The intrinsic binding constants Kb of the ligand and Cu (II) complex, with CT-DNA obtained from UV-vis absorption studies were 1.53×10(4)M(-1) and 3.71×10(5)M(-1), respectively. Moreover the addition of the two compounds to CT-DNA (1:2) led to an increase of the melting temperature of DNA up to around 2.61°C for the ligand and 3.99°C for the Cu (II) complex. The ligand and Cu (II) complex bind to CT-DNA via a partial intercalative, as shown by the experimental data. In addition, the albumin interactions of the two compounds were studied by fluorescence quenching spectra, the results indicating that the binding mechanism is a static quenching process. The in vitro cytotoxicity of the two compounds on three different cancer cell lines was evaluated by MTT assay. The results showed that the copper complex exerted enhanced cytotoxicity compared with the Schiff base ligand; thereby, this complex clearly implies a positive synergistic effect. Furthermore, the copper complex showed a high, selective, and dose-dependent cytotoxicity against cancer cell lines.

Three new ruthenium(ii) complexes of NCN pincer and phenylcyanamide derivative ligands of the formula [Ru(L)(Phphen)(3,5-(NO)pcyd)], 1, [Ru(L)(Mephen)(3,5-(NO)pcyd)], 2, and [Ru(L)(Clphen)(3,5-(NO)pcyd)], 3 (HL: 5-methoxy-1,3-bis(1-methyl-1H-benzo[d]imidazol-2-yl)benzene, 3,5-(NO)pcyd: 3,5-(NO)pcyd, Phphen: 4,7-diphenyl-1,10-phenanthroline, Mephen: 4,7-dimethyl-1,10-phenanthroline, Clphen: 4,7-dichloro-1,10-phenanthroline) have been synthesized and studied as potential photosensitizers (PSs) in photodynamic therapy (PDT). The complexes exhibited promising O production quantum yields comparable with PSs available on the market. The DNA-binding interactions of the complexes with calf thymus DNA have been studied by absorption, emission, and viscosity measurements. All complexes cleave SC-DNA efficiently on photoactivation at 350 nm with the formation of singlet oxygen (O) and hydroxyl radicals (˙OH) in type-II and photoredox pathways. Complexes 1-3 showed very good uptake in cervical cancer cells (HeLa). The compounds studied were found to exhibit low toxicity against HeLa cells (IC > 300 μM) and, remarkably, on non-cancerous MRC-5 cells (IC > 100 μM) in the dark. However, 1 showed very promising behavior with an increment of about 90 times, in its cytotoxicity upon light illumination at 420 nm in addition to very good human plasma stability.

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A series of iridium(iii) arene complexes of naphthoquinone derivatives of the formula [Ir(η-L1)(L2)(3,5-(NO)pcyd)](PF) (L1 = p-methylphenyl)ethynylferrocene; L2 = Lap: lapachol, 1, Plum: plumbagin, 2, Law: lawsone, 3, and Jug: juglone, 4; 3,5-(NO)pcyd = 3,5-dinitrophenylcyanamide) have been synthesized and investigated for their suitability as potential anticancer drugs. The DNA-binding interactions of the complexes with calf thymus DNA have been studied by absorption, emission, and viscosity measurements. Their cytotoxicity against the cancer cell lines including colon adenocarcinoma (HT-29), liver hepatocellular carcinoma (HepG-2), breast (MCF-7), colon carcinoma (HCT-8), and ovary (A2780) is reported. Remarkably, almost all complexes exhibit significant cytotoxic effects towards HepG-2, MCF-7, and HCT-8 cancer cell lines and complex 1 emerged as the most cytotoxic derivative in comparison with other complexes. The complexes 1-4 increase the production of reactive oxygen species (ROS) in MCF-7 cells. The new compounds also inhibit the enzyme thioredoxin reductase activity at nanomolar concentrations. Furthermore, the complexes induce major levels of cancer cell death by apoptosis that is in correlation with activity in cytotoxicity studies.