This work presents the synthesis and characterization of compounds derived from the ruthenium transition metal with the nitrogenous ligand 4-aminopy- ridine (4-ampy). The synthesized compounds were characterized by FT...This work presents the synthesis and characterization of compounds derived from the ruthenium transition metal with the nitrogenous ligand 4-aminopy- ridine (4-ampy). The synthesized compounds were characterized by FTIRmed spectroscopy and TG-DTA thermal analysis. For the cytotoxic evaluation of ruthenium compounds, a 66.0 μM aqueous solution containing the complex and the study of data observed in the biological assessment was performed using variance (ANOVA) analysis, followed by Tukey’s multiple comparisons test. Differences between treatments were considered significant when the p-value was less than 0.05 (p < 0.05). TG/DSC thermal analysis for the first complex suggests a stoichiometry of [Ru(Cl)<sub>3</sub>(4-ampy)(H<sub>2</sub>O)<sub>2</sub>]·1/2H<sub>2</sub>O, which, due to the low solubility in an aqueous medium, was modified to increase its solubility for biological tests. The analysis of the spectra in the medium infrared region (FTIR) for the complex [Ru(Cl)<sub>3</sub>(4-ampy)(H<sub>2</sub>O)<sub>2</sub>]·1/2H<sub>2</sub>O, shows displacements of the bands observed at 1625 - 1566 cm<sup>﹣1</sup> ν(C=C) e (C=N), indicating that coordination to the metallic center occurred by this group. Band displacements were observed in the modified Ru (III) complex, which suggests the presence of the 4-ampy ligand and the coordination by the groups ν(C=C) and (C=N) after the modification. In recent years, researchers worldwide have concentrated on obtaining, developing, and modifying drugs used as chemotherapeutic agents. The evaluation of the cell viability of the modified Ru (III) compound demonstrated cytotoxic effects in the MCF-7 cell line (15.33% ± DP 2.7) but did not affect normal cells (PBMC), which reflects the potential for possible applications.展开更多
Chromium is a heavy metal used for various applications such as in the manufacture of stainless steels, in chemicals for wood treatment, in tanneries, and in the refractory industry. The main problem associated with t...Chromium is a heavy metal used for various applications such as in the manufacture of stainless steels, in chemicals for wood treatment, in tanneries, and in the refractory industry. The main problem associated with the use of chromium in these activities is the considerable volume of contaminated effluent that requires treatment, mainly due to its high mobility and toxicity in its hexavalent form. Immobilization methods arise as an efficient solution for the treatment of these wastes through converting them into inert and stable materials. The present paper aims to investigate Portland cement II’s paste properties with potassium dichromate addition in order to verify the chromium immobilization process. Analyses of moisture content, water absorption, axial compressive strength, and solubilization were done in samples at 7 and 28 days with 0%;0.5%;1.05;1.5%;2.0% and 2.5% potassium dichromate addition. The results showed the influence of this salt in cement hydration reactions, damaging the mechanical behavior and the water absorption capability of the material produced. In the solubilization test, all compositions had >99% efficiency of chromium immobilization in both ages of hydration, thus demonstrating the capability of a cementitious matrix to stabilize this metal.展开更多
文摘This work presents the synthesis and characterization of compounds derived from the ruthenium transition metal with the nitrogenous ligand 4-aminopy- ridine (4-ampy). The synthesized compounds were characterized by FTIRmed spectroscopy and TG-DTA thermal analysis. For the cytotoxic evaluation of ruthenium compounds, a 66.0 μM aqueous solution containing the complex and the study of data observed in the biological assessment was performed using variance (ANOVA) analysis, followed by Tukey’s multiple comparisons test. Differences between treatments were considered significant when the p-value was less than 0.05 (p < 0.05). TG/DSC thermal analysis for the first complex suggests a stoichiometry of [Ru(Cl)<sub>3</sub>(4-ampy)(H<sub>2</sub>O)<sub>2</sub>]·1/2H<sub>2</sub>O, which, due to the low solubility in an aqueous medium, was modified to increase its solubility for biological tests. The analysis of the spectra in the medium infrared region (FTIR) for the complex [Ru(Cl)<sub>3</sub>(4-ampy)(H<sub>2</sub>O)<sub>2</sub>]·1/2H<sub>2</sub>O, shows displacements of the bands observed at 1625 - 1566 cm<sup>﹣1</sup> ν(C=C) e (C=N), indicating that coordination to the metallic center occurred by this group. Band displacements were observed in the modified Ru (III) complex, which suggests the presence of the 4-ampy ligand and the coordination by the groups ν(C=C) and (C=N) after the modification. In recent years, researchers worldwide have concentrated on obtaining, developing, and modifying drugs used as chemotherapeutic agents. The evaluation of the cell viability of the modified Ru (III) compound demonstrated cytotoxic effects in the MCF-7 cell line (15.33% ± DP 2.7) but did not affect normal cells (PBMC), which reflects the potential for possible applications.
文摘Chromium is a heavy metal used for various applications such as in the manufacture of stainless steels, in chemicals for wood treatment, in tanneries, and in the refractory industry. The main problem associated with the use of chromium in these activities is the considerable volume of contaminated effluent that requires treatment, mainly due to its high mobility and toxicity in its hexavalent form. Immobilization methods arise as an efficient solution for the treatment of these wastes through converting them into inert and stable materials. The present paper aims to investigate Portland cement II’s paste properties with potassium dichromate addition in order to verify the chromium immobilization process. Analyses of moisture content, water absorption, axial compressive strength, and solubilization were done in samples at 7 and 28 days with 0%;0.5%;1.05;1.5%;2.0% and 2.5% potassium dichromate addition. The results showed the influence of this salt in cement hydration reactions, damaging the mechanical behavior and the water absorption capability of the material produced. In the solubilization test, all compositions had >99% efficiency of chromium immobilization in both ages of hydration, thus demonstrating the capability of a cementitious matrix to stabilize this metal.
