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This article's objective is the synthesis of new composites based on thermoplastic polyurethane (TPU) and TiO 2 nanowires (NWs) as free-standing films, highlighting their structural and optical properties. The free-standing TPU-TiO 2 NW films were prepared by a wet chemical method accompanied by a thermal treatment at 100 °C for 1 h, followed by air-drying for 2 h. X-ray diffraction (XRD) studies indicated that the starting commercial TiO 2 NW sample contains TiO 2 tetragonal anatase (A), cubic Ti 0.91 O (C), and orthorhombic Ti 2 O 3 (OR), as well as monoclinic H 2 Ti 3 O 7 (M). In the presence of TPU, an increase in the ratio between the intensities of the diffraction peaks at 43.4° and 48° belonging to the C and A phases of titanium dioxide, respectively, is reported. The increase in the intensity of the peak at 43.4° is explained to be a consequence of the interaction of TiO 2 NWs with PTU, which occurs when the formation of suboxides takes place. The variation in the ratio of the absorbance of the IR bands peaked at 765-771 cm -1 and 3304-3315 cm -1 from 4.68 to 4.21 and 3.83 for TPU and the TPU-TiO 2 NW composites, respectively, with TiO 2 NW concentration equal to 2 wt.% and 17 wt.%, indicated a decrease in the higher-order aggregates of TPU with a simultaneous increase in the hydrogen bonds established between the amide groups of TPU and the oxygen atoms of TiO 2 NWs. The decrease in the ratio of the intensity of the Raman lines peaked at 658 cm -1 and 635 cm -1 , which were assigned to the vibrational modes E g in TiO 2 A and E g in H 2 Ti 3 O 7 (I TiO2-A /I H2Ti3O7 ), respectively, from 3.45 in TiO 2 NWs to 0.94-0.96 in the TPU-TiO 2 NW composites, which indicates that the adsorption of TPU onto TiO 2 NWs involves an exchange reaction of TPU in the presence of TiO 2 NWs, followed by the formation of new hydrogen bonds between the -NH- of the amide group and the oxygen atoms of Ti x O 2x-mn , Ti 2 O 3 , and Ti 0.91 O. Photoluminescence (PL) studies highlighted a gradual decrease in the intensity of the TPU emission band, which is situated in the spectral range 380-650 nm, in the presence of TiO 2 NW. After increasing the TiO 2 NW concentration in the TPU-TiO 2 NW composite mass from 0 wt.% to 2 wt.% and 17 wt.%, respectively, a change in the binding angle of the TPU onto the TiO 2 NW surface from 12.6° to 32° and 45.9°, respectively, took place.

In this work, new information concerning the optical properties of black phosphorus (BP) sheets chemically/electrochemically functionalized with diphenyl amine (DPA) and its macromolecular compound (poly(diphenylamine) (PDPA)) in the absence/presence of phosphotungstic acid (PTA) is reported. Raman scattering and FTIR spectroscopy studies indicate that the interaction of BP with PTA leads to the elimination of the P x O y layer onto the surface of the BP sheets. In the case of the chemical interaction of BP with DPA, the reaction product corresponds to DPA chemically functionalized BP sheets having an imino-phosphorane (IP) structure. The electrochemical oxidation of BP sheets chemically functionalized with DPA in the presence of PTA leads to an increase in the weight of P-N bonds as a consequence of the generation of PDPA doped with the PTA heteropolyanions, as shown by FTIR spectroscopy and Raman scattering. This process is evidenced by a shift of the Raman line from 362 cm -1 to 378 cm -1 , assigned to the A 1g mode. This change was explained by taking into account the compression of the layers containing P atoms, which is induced by PDPA macromolecular chains. The decrease in the intensity of the PL spectra of DPA as well as PDPA, in the presence of BP, indicates that BP acts as a PL quenching agent for these compounds. A preferential orientation of the PDPA doped with the PTA heteropolyanions on the surface of BP sheets is highlighted by the variation of the binding angle of the PDPA on the surface of BP sheets from 44.7° to 39.9°.

Melanoma is a skin cancer characterized by rapid growth and spread for which current therapies produce both resistance and increased risk of infection. To develop new anti-melanoma biocompatible species, the series of complexes Cu(N-N)(bzac)(X)⋅nH 2 O (N-N: 1,10-phenanthroline/2,2'-bipyridine, Hbzac: 1-phenyl-1,3-butanedione, X: NO 3 /ClO 4 , and n = 0, 1) was studied. Single-crystal X-ray diffraction revealed a mononuclear structure for all complexes. The ability of the complexes to scavenge or trap reactive oxygen species such as O 2 ⋅ - and HO⋅ was proved by EPR spectroscopy experiments. All complexes inhibited B16 murine melanoma cells in a dose-dependent and nanomolar range, but the complexes with 1,10-phenanthroline were more active. Moreover, comparative activity on B16 and healthy BJ cells revealed a therapeutic index of 1.27-2.24. Bioinformatic methods were used to calculate the drug-likeness, pharmacokinetic, pharmacogenomic, and pharmacodynamic profiles of the compounds. The results showed that all compounds exhibit drug-likeness features, as well as promising absorption, distribution, metabolism, and excretion (ADME) properties, and no toxicity. The pharmacodynamics results showed that the neutral species appear to be good candidates for antitumor molecular targets (Tyrosyl-DNA phosphodiesterase 1, DNA-(apurinic or apyrimidinic site) lyase or Kruppel-like factor 5). Furthermore, the pharmacogenomic results showed a good affinity of the copper(II) complexes for the human cytochrome. These results recommend complexes bearing 1,10-phenanthroline as good candidates for developing drugs to melanoma alternative treatment.