Search results for "Dox"

Electrolyte-driven electrochemical amplification by poly(thienylacetylene) encapsulated within Zeolite Y

2006

Electrochemical oxidation and reduction of poly(thienylacetylene) encapsulated inside zeolite Y (PTA@Y) exhibit with large anodic and cathodic doping currents with a significant reversibility. Thienyl groups lower the redox potential of polyacetylene chain whereas encapsulation stabilizes the resulting charged radical species blocking undesired post electron-transfer cross-link reactions. Size-exclusion effects associated produces an electrolyte-dependent amplification of currents recorded at PTA@Y-modified electrodes for electrochemical processes involving selected substrates in solution, namely, dinitrobiphenyl and benzidine. Keywords: Poly(thienylacetylene), Zeolite Y, Electrochemistry, …

Cover Feature: Visible Light‐Induced Sulfonylation/Arylation of Styrenes in a Double Radical Three‐Component Photoredox Reaction (Chem. Eur. J. 38/20…

2019

Electrochemical behaviour of poly(neutral red) on an ITO electrode

1998

Abstract The formation of a radical cation, by electrochemical oxidation of the neutral red dye in acidic aqueous solution, is controlled by diffusion towards the electrode surface. This is the initiation step of the electrogeneration, potentiostatic or potentiodynamic, of poly(neutral red) films on an indium–tin oxide (ITO) electrode. The polymeric film is a redox semi-conductor, and shows a microporous membrane-like character. Its electrochemical behaviour depends on the generation process. The hydrogen ions play a double role: first as reactants at electrochemical and acid–base equilibrium, second as counterions of the electrons. The global process of the electron-hopping is limited by t…

Polyaminoacid–doxorubicin prodrug micelles as highly selective therapeutics for targeted cancer therapy

2016

An amphiphilic copolymer carrying high-dose doxorubicin (21% on a weight basis), PHEA–EDA–P,C–Doxo, was prepared by coupling doxorubicin with a biocompatible polyaminoacid through a pH-sensitive spacer. Additional derivatization with 4-pentynoic acid endows it with self-assembling properties by means of π–π stacking. These micelles can be triggered to promptly release drug in lysosomes (∼40% in 12 h) through pH-dependent micelle hydrolysis after uptake. In vitro tests on co-cultures of cancer (MDA-MB 231) and normal (HB-2) breast cells proved that the conjugate was selectively internalized into the former rather than normal cells, exploiting the caveolae-dependent endocytosis pathway, expla…

Investigation of electrode material – Redox couple systems for reverse electrodialysis processes. Part I: Iron redox couples

2012

Abstract The performances of electrodialysis (ED) and reverse electrodialysis (RED) processes depend on several factors, including the nature of the electrode material and of the redox couple adopted to make possible the conversion between electric power and chemical potential. In this paper, the possible utilization of iron-based redox couples (FeCl3/FeCl2, hexacyanoferrate(III)/hexacyanoferrate(II) and Fe(III)-EDTA/Fe(II)-EDTA) on graphite and DSA electrodes for RED processes was studied by a detailed experimental investigation. The hexacyanoferrate(III)/hexacyanoferrate(II) system was stable for long time (more than 12 days) in the absence of light and oxygen at high redox couple concent…

ChemInform Abstract: New Reactions of Amino-Functionalized 3-Vinyl-1H-indoles and Tetrahydropyridin-4-yl Analogues with Dienophiles.

2010

Reactions of 3-[2-(morpholin-4-yl)vinyl]-1H-indole (1), the 1,2-dihydro-9H-carbazole 2, as well as the 3-(tetrahydropyridin-4-yl)-1H-indoles 3a and 3b with some carbo- and heterodienophiles are described. The scope and limitations of the synthetic utility of these amino- (or homoamino)-functionalized 3-vinyl-1H-indoles are reported and some MO calculations for the qualitative prediction of their reactivities are presented. The reactions gave rise to substitution products, redox products, Diels-Alder adducts, ene adducts, and Michael-type adducts (Schemes 2 and 3).

Hot electron injection into aqueous electrolyte solution from thin insulating film-coated electrodes

1998

Hot electron injection into aqueous electrolyte solution was studied with electrochemiluminescence and electron paramagnetic resonance (EPR) methods. Both methods provide further indirect support for the previously proposed hot electron emission mechanisms from thin insulating film-coated electrodes to aqueous electrolyte solution. The results do not rule out the possibility of hydrated electron being as a cathodic intermediate in the reduction reactions at cathodically pulse-polarized thin insulating film-coated electrodes. However, no direct evidence for electrochemical generation of hydrated electrons could be obtained with EPR, only spin-trapping experiments could give information about…

Oxidomolybdenum(IV), ‐(V), ‐(VI) Complexes with Relevance to Molybdenum Enzymes: Oxygen Atom Transfer, Redox Chemistry and EPR Spectroscopy

2010

The cis-dioxidomolybdenum(VI) complex Mo(NN′)2O2 (1) [(NN′) = N-(4-hydroxyphenyl)-2-pyrrolatocarbaldimine] transfers one oxygen atom to phosphanes PMenPh3–n (n = 0–3) to give quantitatively the respective phosphane oxides OPMenPh3–n (OAT, oxygen atom transfer). The kinetics of these OAT reactions has been investigated spectrophotometrically. When offering excess PMenPh3–n (n = 1–3), oxido(phoshane)molybdenum(IV) complexes Mo(NN′)2O(PMenPh3–n) 5a–5c are isolated and characterized by multinuclear NMR spectroscopy (1H, 13C, 31P, 15N), IR spectroscopy, UV/Vis spectroscopy and mass spectrometry. The redox chemistry of the molybdenum(IV) complexes 5a–5c and of molybdenum(VI) complex 1 has been pr…

Solvent-Independent Electrode Potentials of Solids Undergoing Insertion Electrochemical Reactions: Part I. Theory

2012

A formally solvent-independent redox system can be theoretically defined using the Lovric and Scholz modeling of the voltammetry of microparticles for ion-insertion solids. The proposed theory is based on the extra-thermodynamic assumptions that no net charge accumulates at the solid|electrolyte interface and the assumption that the structure of the solid and the ion binding remain unaffected by the solvent. Under voltammetric conditions, the corresponding redox potential can be estimated from voltammetric and chronoamperometric data assuming electrochemical reversibility and diffusive charge transport in the solution and solid phases, also taking into account ion partition (electrolyte/sol…

An Iron-Based Molecular Redox Switch as a Model for Iron Release from Enterobactin via the Salicylate Binding Mode

2001

The iron release mechanism from protonated ferric enterobactin [Fe(III)(enterobactinH(3))] via the salicylate binding mode was probed. For this purpose, a tripodal dodecadentate ligand incorporating three salicylamide (OO) and three bipyridine (NN) binding sites was synthesized as well as iron complexes thereof. It was shown that a ferric ion coordinates selectively to the hard salicylamides and a ferrous ion binds to the softer bipyridines. Upon reduction or oxidation, the iron translocates reversibly and intramolecularly from one site to the other, thus displaying switchlike properties. Both states were characterized by cyclic voltammetry and visible and Mössbauer spectroscopy. The Mössba…