Search results for " intercalation"
showing 10 items of 14 documents
The interaction of native calf thymus DNA with FeIII-dipyrido[3,2-a:2’,3’-c]phenazine
2008
The mono and bis dipyrido[3,2-a:2',3'-c]phenazine (dppz) adducts of iron(III) chloride, i.e. [Fe(dppz)]Cl(3) and [Fe(dppz)(2)]Cl(3), have been synthesized and characterized. The interaction of the Fe(III)dppz hydrolyzed aquo complex with native calf thymus DNA has been monitored as a function of the metal complex-DNA molar ratio, by variable temperature UV absorption spectrophotometry, circular dichroism (CD) and fluorescence spectroscopy. The results obtained in solution at various ionic strength values give support for a tight intercalative binding of the Fe(III)dppz cation with DNA. In particular, the appearance of induced CD bands, caused by the addition of Fe(III)dppz, indicate the exi…
Electromembrane Processes: Experiments and Modelling
2021
This Special Issue of Membranes journal focuses on electromembrane processes and is motivated by the increasing interest of the scientific community towards their characterization by experiments and modelling for several applications [...]
Confinement effects on the interactions of native DNA with Cu(II)-5-triethyl ammonium methyl salicylidene orto-phenylendiiminate in C12E4 liquid crys…
2008
Confinement effects of native calf thymus DNA interacting with the complex Cu(ii)-5-(triethylammoniummethyl)salicylidene ortho-phenylendiiminate (CuL(2+)) perchlorate in tetraethylene glycol monododecyl ether (C(12)E(4)) liquid crystals have been investigated by UV absorption spectrophotometry, circular dichroism (CD) and small angle X-ray scattering (SAXS). The results indicate the occurrence of dramatic structural changes of both the DNA and the CuL(2+)-DNA system, when going from aqueous solution to C(12)E(4) liquid crystals, due to confinement constrains imposed by the closed structure of C(12)E(4) reverse micelles. Further marked departures from the behaviour observed in aqueous soluti…
The interaction of native DNA with iron(III)- N ,N'-ethylene-bis(salicylideneiminato)-chloride.
2004
Abstract The interaction between native calf thymus deoxyribonucleic acid (DNA) and Fe III - N , N ′ -ethylene-bis (salicylideneiminato)-chloride, Fe(Salen)Cl, was investigated in aqueous solutions by UV–visible (UV–vis) absorption, circular dichroism (CD), thermal denaturation and viscosity measurements. The results obtained from CD, UV–vis and viscosity measurements exclude DNA intercalation and can be interpreted in terms of an electrostatic binding between the Fe(Salen) + cation and the phosphate groups of DNA. The trend of the UV–vis absorption band of the Fe(Salen)Cl complex at different ratios [DNA phosphate ]/[Fe(Salen)Cl] and the large increase of the melting temperature of DNA in …
Combined spectroscopic and theoretical analysis of the binding of a water-soluble perylene diimide to DNA/RNA polynucleotides and G-quadruplexes.
2021
We present here a combined spectroscopic and theoretical analysis of the binding of N,N’-bis(2-(1-piperazino)ethyl)-3,4,9,10-perylenetetracarboxylic acid diimide dichloride (PZPERY) to different biosubstrates. Absorbance titrations and circular dichroism experiments, melting studies and isothermal calorimetry (ITC) titrations reveal a picture where the binding to natural double-stranded DNA is very different from that to double and triple-stranded RNAs (poly(A)∙poly(U) and poly(U)∙poly(A)⁎poly(U)). As confirmed also by the structural and energetic details clarified by density functional theory (DFT) calculations, intercalation occurs for DNA, with a process driven by the combination of aggr…
Long-Term Stability of TiS2–Alkylamine Hybrid Materials
2022
Layered TiS2 intercalated with linear alkylamines has recently attracted significant interest as a model compound for flexible n-type thermoelectric applications, showing remarkably high power factors at room temperature. The thermal and, particularly, environmental stability of such materials is, however, a still an open challenge. In this paper, we show that amine-intercalated TiS2 prepared by a simple mechanochemical process is prone to chemical decomposition through sulfur exsolution, and that the presence of molecular oxygen is likely to mediate the decomposition reaction. Through computational analysis of the possible reaction pathways, we propose that Ti-N adducts are formed as a con…
Molecular modeling of intercalation complexes of antitumor active 9-aminoacridine and a [d, e]-anellated isoquinoline derivative with base paired deo…
1996
Intercalators are molecules capable of sliding between DNA base pairs without breaking up the hydrogen bonds between the DNA bases. On the basis of molecular mechanics calculations structural, models of B-DNA tetranucleotide intercalation complexes of some cytostatic active 9-aminoacridines and of a [d, e]-anellated isoquinoline derivative are presented. The drug complexes are stabilized by energetically favouredvan der Waals interactions and by selective hydrogen bonds between the side chains of the drugs and the DNA bases. Semiempirical quantum chemistry calculations revealed that the chromophoric system of the intercalators is able to form π,π-charge-transfer interactions with the purine…
(Dipyrido[3,2-a:2',3'-c]phenazine)(glycinato)copper(II) perchlorate: a novel DNA-intercalator with anti-proliferative activity against thyroid cancer…
2012
Abstract A novel copper(II) heteroleptic complex of dipyrido[3,2-a:2′,3′-c]phenazine (dppz) and glycinato (gly) as chelating ancillary ligand, [Cu(dppz)(gly)]ClO 4 ( 1 ), was synthesized and characterized. X-ray crystallography revealed that the coordination geometry of the cationic [Cu(dppz)(gly)] + unit is hexacoordinated and shows a distorted octahedral coordination geometry in the solid state, with the N,N and N,O chelating atoms of dppz and glycinato, respectively, in the square plane and in which the planar units are connected in a monodimensional polymeric array by the apical copper coordination of the second carboxylic oxygen atom. Biological assays showed that 1 exhibits a remarkab…
Electrochemical Fabrication and Physicochemical Characterization of Metal/High-k Insulating Oxide/Polymer/Electrolyte Junctions
2014
Photoelectrochemical polymerization of poly(3,4-ethylenedioxythiophene), PEDOT, was successfully realized on anodic film grown to 50 V on magnetron sputtered Ti-6 atom % Si alloys. Scanning electron microscopy allowed us to evidence formation of compact and uniform polymer layers on the oxide surface. Photoelectrochemical and impedance measurements showed that photopolymerization allows one to grow PEDOT in its conducting state, while a strong cathodic polarization is necessary to bring the polymer in its p-type semiconducting state. Information on the optical and electrical properties of metal/oxide/polymer/electrolyte junctions proves that PEDOT has promising performance as an electrolyte…