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A novel, simple, sensitive, and precise spectrofluorometric assay of cancer antigen [CA 125] is described. This modality is based on monitoring the quenching of the luminescence intensity at 790 nm of the phthalocyanine fluorophore, in a nanocomposite comprising the fluorophore and cationic polystyrene, which results from interaction with CA 125. The remarkable quenching of the luminescence intensity of the Ni-phthalocyanine complex doped in PS matrix by various concentrations of CA 125 was successfully utilized as an optical sensor for the determination of CA 125 in different serum samples of ovarian disease. The performance of the designed biosensor is determined through monitoring the quenching of the luminescence intensity at 790 nm by cancer antigen 125 after excitation at 685 nm, pH 7.3 in water. The calibration plot was achieved over the concentration range 1.0 × 10−2 – 127 U mL−1 CA-125 with a correlation coefficient of 0.99 and detection limit of 1.0 × 10−4 U mL−1. The mechanism of the interaction between the nano thin film nickel(II)phthalocyanine and CA-125 was discussed. A significant correlation between the proposed method for the assessment of CA 125 and the standard method was applied to patients and controls. Image 1 • Nano optical sensor Ni-phthalocyanine complex was prepared. • The optical sensor is used for assessment of CA-125. • The assessment of CA-125 in serum samples of ovarian cancer disease. [ABSTRACT FROM AUTHOR]

Ni- and Cu/alumina powders were prepared and characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), and N2 physisorption isotherms were also determined. The Ni/Al2O3 sample reveled agglomerated (1 μm) of nanoparticles of Ni (30–80 nm) however, NiO particles were also identified, probably for the low temperature during the H2 reduction treatment (350 °C), the Cu/Al2O3 sample presented agglomerates (1–1.5 μm) of nanoparticles (70–150 nm), but only of pure copper. Both surface morphologies were different, but resulted in mesoporous material, with a higher specificity for the Ni sample. The surfaces were used in a new proposal for producing copper and nickel phthalocyanines using a parallel-plate reactor. Phthalonitrile was used and metallic particles were deposited on alumina in ethanol solution with CH3ONa at low temperatures; ≤60 °C. The mass-transfer was evaluated in reaction testing with a recent three-resistance model. The kinetics were studied with a Langmuir-Hinshelwood model. The activation energy and Thiele modulus revealed a slow surface reaction. The nickel sample was the most active, influenced by the NiO morphology and phthalonitrile adsorption.

Ni- and Cu/alumina powders were prepared and characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), and N2 physisorption isotherms were also determined. The Ni/Al2O3 sample reveled agglomerated (1 μm) of nanoparticles of Ni (30--80 nm) however, NiO particles were also identified, probably for the low temperature during the H2 reduction treatment (350 °C), the Cu/Al2O3 sample presented agglomerates (1-1.5 μm) of nanoparticles (70-150 nm), but only of pure copper. Both surface morphologies were different, but resulted in mesoporous material, with a higher specificity for the Ni sample. The surfaces were used in a new proposal for producing copper and nickel phthalocyanines using a parallel-plate reactor. Phthalonitrile was used and metallic particles were deposited on alumina in ethanol solution with CH3ONa at low temperatures; ≤60 °C. The mass-transfer was evaluated in reaction testing with a recent three-resistance model. The kinetics were studied with a Langmuir-Hinshelwood model. The activation energy and Thiele modulus revealed a slow surface reaction. The nickel sample was the most active, influenced by the NiO morphology and phthalonitrile adsorption. [ABSTRACT FROM AUTHOR]

Abstract: The properties of polymer blend prepared by the polymerization of 3,4-(ethylenedioxy)thiophene in the presence of iron(III) toluensulfonate (PEDOT:PTSA) as well as the interface properties of the NiPc/PEDOT:PTSA system were investigated by X-ray and UV photoemission spectroscopies. The results are compared with those studied previously for NiPc/PEDOT:PSS (poly[3,4-(ethylenedioxy)thiophene]-sulfonated polystyrene) and NiPc/ITO interfaces. The non-reactive NiPc/Au interface was used as a reference for the determination of the Fermi level position in NiPc. Different properties observed for the NiPc/PEDOT:PTSA and NiPc/PEDOT:PSS interfaces are discussed in the frame of different chemical structures of both polymers. [Copyright &y& Elsevier]

Abstract: The electrical properties: DC-electrical conductivity (σ DC), AC-electrical conductivity (σ AC), dielectric permittivity (ε′) and dielectric loss (ε″) for pure polymethylmethacrylate (PMMA) and mixed with phthalocyanine, Ni-phthalocyanine and hematoporphyrin IX chloride laser dyes have been investigated. The conductivity values for all polymer–dye samples are higher than that of the pure PMMA. For all investigated samples, at the constant temperature, the frequency dependence of (σ AC) was found to obey the relation (σ AC)= Aωs. The results are discussed according to the correlated barrier hopping CBH mechanism from which the Coulomb well barrier of charge carriers (W M) was calculated. For the dye-doped samples, the hematoporphyrin IX chloride mixed sample showed the larger value of (W M) compared with the others. At all frequencies, ε' values for doped samples are higher than that of pure one. This is due to a free volume enhancement offered by the large size of the dye molecule. Also, the addition of dyes to PMMA causes an increase in the intensity of the loss peak (ε″) accompanied by a shift in its position. The effect of chemical structure of investigated dyes on the electrical properties is discussed. [Copyright &y& Elsevier]

Abstract: Luminescent solar concentrator samples using polymethylmethacrylate (PMMA) as the matrix with phthalocyanine, nickel-phthalocyanine and hematoporphyrin IX dichloride laser dyes were prepared by a casting method. Optical absorption measurements were carried out at room temperature across the 200–900nm wavelength region both before and after the samples were exposed to sunlight for two weeks. The degradation of PMMA–dye samples, measured by absorption, was found to obey a first-order kinetic equation. Values of the optical band gaps (E g) have been obtained for the direct allowed transitions before and after the samples were exposed to sunlight. The tail width of localized states in the band gap (E u) was calculated from Urbach’s formula. Photodegradation studies revealed that the phthalocyanine dye systems are the most stable. Emission spectra and quantum efficiency were also investigated, and phthalocyanine dyes were shown to have a lower Stokes shift and a higher fluorescence quantum yield (Q f) than the hematoporphyrin IX dichloride. Collectively, these results suggest that PMMA doped with phthalocyanines provide the better system for use in fluorescent solar collector systems. [Copyright &y& Elsevier]

Optical properties of thermally evaporated nickel phthalocyanine thin films have been characterised using spectrophotometric measurements of transmittance and reflectance in spectral range 200–2100 nm. The refractive index n and the absorption index k were calculated. Some of the optical absorption parameters, namely optical absorption coefficient (α), molar extinction coefficient (εmolar), oscillator strength (f), electric dipole strength (q2) and absorption half bandwidth (Δλ) of the principal optical transitions have been also evaluated. The analysis of the spectral behaviour of the absorption coefficient (α), in the absorption region revealed indirect transitions. The fundamental and the onset energy gaps were estimated as 2.77±0.02 eV and 1.58±0.01 eV, respectively. According to the analysis of dispersion curves, the dielectric constants and dispersion parameters were obtained. The absorption measurements recorded in the UV–VIS region show two well defined absorption bands of phthalocyanine molecule, namely the Soret band (B) and the Q band. The Q band shows its characteristic splitting (Davydov splitting), and ΔQ was obtained as 0.21 eV. Discussion of the obtained results and their comparison with the previous published data are also given. [ABSTRACT FROM AUTHOR]

The electrooxidation of 2-chlorophenol (2-CP) on poly-nickel tetrasulfophthalocyanine (polyNiTSPc) modified glassy carbon (GC) and indium tin oxide (ITO) electrodes was studied by cyclic voltammetry and in situ UV–Vis transmission spectroscopy. The polyNiTSPc films were characterized by XPS and AFM, both before and after reaction with 2-CP. The results indicate that NiTSPc polymerizes at both GC and ITO electrodes, apparently retaining its phthalocyanine structure in which the Ni atoms play a role similar to that in Ni(OH)2 films. In the oxidation of 2-CP at polyNiTSPc-modified electrodes the electrode fouling by a layer of polymerized 2-CP oxidation products (polyCP) is weaker than on the bare GC electrode, probably because the polyCP layer formed on polyNiTSPc–ITO is very rough, as indicated by AFM, thus allowing the passage of CP molecules to the polyNiTSPc film. [Copyright &y& Elsevier]