Stanislaw Biniak

Activated carbon F-400 was modified by using different oxidation agents: nitric acid, sulfuric acid, and ozone. The influence of the type of carbon surface groups on adsorption effectiveness towards selected aromatic compounds was analyzed. The commercial carbon F-400 was deashed and modified, and the obtained materials were characterized by using different techniques to determine their textural, thermal, morphological, and surface properties: low-temperature adsorption/desorption isotherms of nitrogen, scanning electron microscopy (SEM), Boehm titration, and Fourier transform infrared spectroscopy (FTIR). The adsorption properties towards four aromatic compounds, i.e., toluene, 4-nitrotoluene, nitrobenzene, and 4-nitrobenzoic acid, were evaluated based on isotherm measurements. Adsorption equilibrium data were analyzed by applying the generalized Langmuir isotherm. The influence of carbon surface groups and adsorbate functional groups in interaction mechanisms was discussed. It was found there was a strong effect of oxidation on adsorption efficiency. The adsorption capacity of modified activated carbon F-400 strongly depends on the type of oxidant used, e.g., in the case of toluene, the use of ozone as an oxidant gives a sorption capacity of 5.51 mmol/g, and of nitric acid—4.20 mmol/g.

Functionalized multiwalled carbon nanotubes with [IndH][ trans -RuCl ₄ (Ind) ₂ ].

Two mononuclear ruthenium(III) mer- and fac-isomers of the formula [RuCl₃(PPh₃)(dmpbt)] (where PPh₃ = triphenylphosphine, dmpbt = 2-(3,5-dimethylpyrazoll-yl)benzothiazole) have been synthesised from the reaction of [RuCl₃(PPh₃)₃] with a bidentate ligand – dmpbt. Appropriate reaction conditions allowed obtaining the two isomers separately without separation techniques. X-ray crystallography has determined the crystal and molecular structures of the new complexes. mer-Ru(III) (1) crystallised in the monoclinic P2(1)/n group, and fac-Ru(III) (2, 2′) in the triclinic P space group. The composition of the ruthenium coordination sphere was confirmed and characterised using spectroscopic techniques (FT-IR, UV-vis and EPR), elemental analysis and mass spectrometry (MS-FAB). The structures of the complexes obtained were analysed using X-ray and other spectroscopic methods (IR and UV-vis). The electrochemical properties of the ligand and the complex compound were identified using cyclic voltammetry, determining the potential and charge of faradaic processes. Both isomers are redox active and display quasi-reversible metal centered redox processes for the Ru(III)/Ru(II) pair. Moreover, preliminary tests of their biological activity were performed. The cytotoxicity of these compounds has been tested for human lung carcinoma (A549), chronic myelogenous leukemia (K562), human cervix carcinoma (HeLa) cells, acute lymphoblastic leukemia (MOLT-4), human breast adenocarcinoma cell line (MCF-7) and normal human umbilical vein endothelial cells (HUVEC). The ability to induce apoptosis has been demonstrated in caspase 3/7 activity assay. In addition, the lipophilicity of both isomers was described by a partition coefficient, log P, values of which were estimated by the shake-flask method. The interesting and promising preliminary results of the biological and chemical activities of the new octahedral mer/fac Ru(III) complexes motivate further in vitro and in vivo studies.