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Two new nitrato complexes of zinc and nickel with 1,4,8,11-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc), have been synthesized and characterized. The IR spectral peaks showed that the coordinated and ionic nitrate ions are in agreement with the formula proposed by elemental analysis. Conductometric titrations predicted methanol to be a convenient solvent for synthesis and revealed the stoichiometry of the complexes, while molar electrical conductivities indicated a 1 : 3 complex electrolyte type for the zinc complex, and a 1 : 2 complex electrolyte type for the nickel complex. The optimized complex structure was obtained by molecular modeling and density functional theory calculations. The biological activity of the novel complexes was examined by screening eight different bacterial strains and two cancer cell lines. The zinc complex showed better antimicrobial activity against the bacterial strains, while the complexes did not show significance antiproliferative activity toward cancer cells MCF-7 and MDA-MB-231.

Here, we report the design of a disposable single-drop voltammetric sensor for the quantitative determination of antipsychotic drug trifluoperazine (TFP). The sensor was built using inkjet-printed carbon nanotube (CNT) electrodes, which were modified with dimercaptosuccinic acid (DMSA)-coated magnetite nanoparticles uniformly dispersed over reduced graphene oxide nanosheets (DMSA/Fe3O4/RGO). The used modifying materials were characterized by electron microscopy techniques (transmission electron microscopy (TEM) and field emission-scanning electron microscopy (FE-SEM)), X-ray powder diffraction, ζ-potential measurements, dynamic light scattering (DLS), and electrochemical methods (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)). The developed sensor, best operated at pH 7 in the Britton-Robinson buffer solution (BRBS), shows linear electrocatalytic activity with TFP in the concentration range of 1-50 μM, a low detection limit of 0.54 μM, and excellent selectivity, repeatability, and reproducibility with an relative standard deviation (RSD) of 2.4%. A voltammetric approach using square wave voltammetry (SWV) is a sensitive technique under optimized conditions for the analytical determination of submicromolar amounts of TFP. Bare CNT and RGO- and DMSA/Fe3O4-modified CNT electrodes showed lower electrocatalytic activity than the DMSA/Fe3O4/RGO/CNT electrode. The development of this kind of TFP sensor based on nanoparticle-decorated graphene nanosheets can offer a tool for point-of-care applications as sensors in biomedicine.

Mefenamic acid and indomethacin, medicaments belonging to the group of non-steroidal anti-inflammatory agents, were determined separately and simultaneously at anodically prepared BDDE. Differential pulse voltammetry was used to establish simple and fast analytical procedure based on electrooxidation of mefenamic acid at 0.6 V and indomethacin at 1.0 V (and 1.1 V). At optimal conditions, it was suitable for highly sensitive and selective determination of these compounds with LODs comparable to previously reported modified electrodes. Additionally, considering the importance of these compounds, we proposed precise and accurate quantification of these species based on green and simple pre-treatable electrochemical sensor. The effect of interfering agents (tablet ingredients and vitamins) was appeared to be negligibly confirming a favourable selectivity of the method. The proposed method was analytically applied by simultaneously determining mefenamic acid and indomethacin in pharmaceutical formulations. © 2020 Elsevier B.V.

In recent years, the search for effective anticancer compounds based on transition metal complexes has been the focus of medical investigations. The synergy between the ruthenium(II) and N-alkylphenothiazine counter-ions (chlorpromazine hydrochloride, thioridazine hydrochloride and trifluoperazine dihydrochloride, respectively) through the formation of three different complexes (1–3) was investigated. We explored whether the selected counter-ions and complexes might affect redox homeostasis and genome integrity of normal human blood cells, and induce an inhibition of Na+/K+-ATPase and AChE at pharmacologically relevant doses. Our results have shown that counter-ions and complexes did not affect the activity of Na+/K+-ATPase, while AChE activity was inhibited in a dose-dependent manner. All investigated compounds disturbed the viability and redox homeostasis of lymphocytes. Complexes 1 and 2 displayed potent cytotoxic and prooxidant action while complex 3 behaved as a weaker genotoxic inducer. Still, the tested complexes appeared to be less genotoxic and more cytostatic than the corresponding counter-ions. The effects of selected complexes were also tested in PC12 and U2OS cancer cells with special attention being given to the ability of phenothiazines to affect dopamine D2 receptors. Using the confocal laser scanning microscopy, we observed that all the complexes reduced cell viability. Although all investigated complexes have been bound to the dopamine receptor D2-eGFP, only complex 3 reduced its surface density and increased its lateral mobility in investigated cell lines. Albeit the role of alternative targets for complex 3 cannot be ruled out, its effects should be further examined as potential treatment strategy against cancer cells that overexpress D2.

A simple and fast method for determination of two phenothiazine drugs, chlorpromazine (CPZ) and thioridazine (TDZ), at the boron-doped diamond electrode (BDDE) was proposed. Oxidation peaks on potentials higher than 1 V were used for quantitation of investigated phenothiazines due to better selectivity over common interfering compounds in urine. Differential pulse voltammetry was applied for trace determination of CPZ and TDZ, in Britton-Robinson buffer solution at optimal pH. Under optimized DPV conditions a linear analytical curve was obtained from 1.0x10(-7) to 4.0x10(-5) M with a detection limit of 0.3x10(-7) M (for CPZ) and in the concentration range of 2x10(-7) M to 4.0x10(-5) M, with a detection limit of 1.2x10(-7)M (for TDZ). The applicability of the method was proved by determination of CPZ and TDZ by proposed procedures in spiked urine samples. The electrochemical behavior of those two important tranquilizers in different solvents was described, exploring the possibility of simultaneous determination.