Nano-scale drug delivery systems for antiarrhythmic agents.

Arrhythmia means the heart is beating too fast, too slow, or with an irregular pattern. Due to the side effects and low bioavailability of many antiarrhythmic drugs, nano-encapsulation has been widely used for their targeted delivery. Lipid nanocapsules, nano liposomes, nano niosomes, solid lipid nanoparticles and polymeric nanoparticles are common nano-carriers used for this purpose. The aim of this article is to summarize some of nano systems used for the specific delivery of antiarrhythmic agents to target tissues. At first, nanotechnology and its applications in drug delivery are described in brief. Then, some information on arrhythmias and antiarrhythmic drugs are provided. Finally, the nano drug delivery systems are explained and examples of their applications in encapsulation of antiarrhythmic drugs are presented.

Synthesis and structure elucidation of novel salophen-based dioxo-uranium(VI) complexes: In-vitro and in-silico studies of their DNA/BSA-binding properties and anticancer activity.

The synthesis and characterization of three dioxo U(VI) complexes, [UO2(L1)(OH2)], [UO2(L2)DMF], and [UO2(L2)DMSO], [L1]2- = 1,1'-(4-methyl-1,2-phenylenebis (nitrilomethylidyne))di-2-naphtholate: [L2]2- = 1,1'-(o-phenylenebis (nitrilomethylidyne)) di-2-naphtholate, are reported. Elemental analysis, FT-IR, 1HNMR, UV-Vis spectroscopy, molar conductivity and single crystal X-ray diffraction were used to characterize the complexes. It was found that the complexes adopt a distorted pentagonal bipyramidal coordination geometry. The interaction of the synthesized complexes with DNA and bovine serum albumin was thoroughly investigated using both experimental and theoretical studies. UV-Vis absorption and fluorescence quenching techniques were applied to determine the binding parameters as well as the mechanism of the interaction of each complex with DNA and the protein. The results obtained suggested that interaction of the complexes with DNA occurred through partial intercalation into the minor grooves of DNA with binding constants in the range of 0.661 × 105-1.56 × 105 M-1. In addition, interaction of the complexes with bovine serum albumin quenched the fluorescence emission of the tryptophan residues of the protein binding constants and thermodynamic parameters were obtained from the fluorescence quenching experiments at different temperatures. The values of binding constants revealed moderate interactions between the synthesized complexes and the protein suggesting that this protein could act as a suitable vehicle for transportation of the compounds. The results of molecular docking confirmed those of the experimental studies. The anticancer properties of the title complexes were also evaluated through a study of the in vitro cytotoxicity of the compounds against the HT-29 and MCF-7 cancer cell lines and the DPSC normal cell line using an MTT assay.

In vitro and in silico studies of the interaction of three tetrazoloquinazoline derivatives with DNA and BSA and their cytotoxicity activities against MCF-7, HT-29 and DPSC cell lines.

In this study, the interaction of three [1,2,3,4]tetrazolo[5,1-b]-quinazolin-8-one derivatives with salmon sperm DNA and BSA was investigated experimentally and theoretically. Fluorescence and absorption spectroscopy techniques were applied to determine the probable interaction mechanism and correlated binding constants and thermodynamic parameters. It was found that the compounds intercalate into the DNA duplex via minor groove in a moderately strong fashion with the binding constants of 104M-1. The values of binding constant for the interaction with BSA at different temperatures were also calculated to be in the range of 1.06×103-3.54×108M-1 indicating the relatively high propensity of the compounds to BSA. In vitro cytotoxicity studies on the effect of the compounds on MCF-7 and HT-29 cancerous cell lines as well as DPSC normal cell line were performed using MTT assay. It was observed that the compounds exhibited selective inhibitory effect against cancer cell growth. Moreover, each of the title compounds was separately docked to DNA and BSA using Autodock Vina as a molecular docking program. The obtained theoretical results were in good agreement with those obtained from Experimental studies.

Synthesis, characterization, crystal structure, DNA and BSA binding, molecular docking and in vitro anticancer activities of a mononuclear dioxido-uranium(VI) complex derived from a tridentate ONO aroylhydrazone.

A mononuclear dioxido-uranium(IV) complex [UO2(L)(DMSO)2], was prepared from the reaction of (2-hydroxy-3-methoxybenzylidene)benzohydrazide [HL] with UO2(OAc)2·2H2O in DMSO. The obtained complex was fully characterized. Single crystal X-ray diffraction analysis of [UO2(L)(DMSO)2] revealed that U(VI) ion has been coordinated by ONO donor atoms of the dianionic ligand (L(2-)), oxo groups and two DMSO molecules in a pentagonal bipyramid geometry. In addition, interactions of the complex with salmon sperm DNA and bovine serum albumin (BSA) were thoroughly investigated using UV-vis absorption, voltammetry and molecular docking methods. The experimental studies showed an intercalative mode of interaction between the complex and DNA. Experiments on BSA interaction indicated a change in the polarity of the environment surrounded the complex as a result of the interaction between BSA and [UO2(L)(DMSO)2]. Finally, MTT assays indicated that the U(VI) complex had excellent cytotoxicity against human carcinoma cell lines of MCF-7, HPG-2, and HT-29, with IC50 values of 8.4, 10.6 and 10.0µM, respectively.

Synthesis, characterization, X-ray crystal structure, DFT calculation, DNA binding, and antimicrobial assays of two new mixed-ligand copper(II) complexes.

Two new Cu(II) complexes, [Cu(L)(phen)] (1), [Cu(L)(bipy)] (2), where L(2-)=(3-methoxy-2oxidobenzylidene)benzohydrazidato, phen=1,10 phenanthroline, and bipy=2,2' bipyridine, were prepared and fully characterized using elemental analyses, FT-IR, molar conductivity, and electronic spectra. The structures of both complexes were also determined by X-ray diffraction. It was found that, both complexes possessed square pyramidal coordination environment in which, Cu(II) ions were coordinated by donor atoms of HL and two nitrogens of heterocyclic bases. Computational studies were performed using DFT calculations at B3LYP/6-311+G(d,p) level of theory. DNA binding activities of these complexes were also investigated using electronic absorption, competitive fluorescence titration and cyclic voltammetry studies. The obtained results indicated that binding of the complexes to DNA was of intercalative mode. Furthermore, antimicrobial activities of these compounds were screened against microorganisms.

Combined experimental and theoretical studies on the X-ray crystal structure, FT-IR, 1H NMR, 13C NMR, UV-Vis spectra, NLO behavior and antimicrobial activity of 2-hydroxyacetophenone benzoylhydrazone.

A Schiff base ligand, 2-hydroxyacetophenone benzoylhydrazone (HL) was synthesized and fully characterized with FT-IR, elemental analyses, UV-Vis, (1)H NMR and (13)C NMR spectra. DFT calculations using B3LYP/6-31+G(d,p) and PW91/DZP are performed to optimize the molecular geometry. Optimized structures are used to calculate FT-IR, UV-Vis, (1)H NMR and (13)C NMR spectra of the compound. Also the energies of the frontier molecular orbitals (FMOs) have been determined. The results obtained from the optimization and spectral analyses are in good agreement with the experimental data. To investigate non-linear optical properties, the electric dipole moment (µ), polarizability (α) and molecular first hyperpolarizability (ß) were computed. The linear polarizabilities and first hyperpolarizabilities of the studied molecule indicate that the compound can be a good candidate of nonlinear optical materials. In addition, the minimal inhibitory concentration (MIC) of this compound against Staphylococcus aureus, and Candida albicans was determined.