Anode oxidation of copper in alkali media in the presence of glycine, α-alanine,and asparagine acid

The effect of glycine, α-alanine, and asparagine acid on the kinetics of anode processes occurring for copper in alkali electrolytes is studied. The experiments are performed in a background solution of 1 × 10⁻² M NaOH (pH 12). The concentrations of glycine and α-alanine are varied in the range of 1 × 10⁻⁶-1 × 10⁻¹ M, and the concentration of asparagine acid is varied in the range of 1 × 10⁻⁵-1 × 10⁻³ M. All amino acids used in this work have been found to stimulate anode oxidation of passivated copper, initiating local activation (LA) of the metal. Depending on the nature of amino acids, this effect occurs in various concentration ranges: for glycine and α-alanine, it takes place at c= 5 × 10⁻³-2 × 10⁻² M, while for asparagine acid, at c = 1 × 10⁻⁵−1 × 10⁻³ M. In addition to this general regularity, several individual peculiarities have been revealed: in the systems containing a monobasic amino acid additive, local activation occurs at E = 0.10–0.20 V, while in the presence of a dibasic amino acid, the local activation is observed at two potentials, E _LA¹ = 0.20–0.30 V and = E _LA² = 0.80–0.90 V, separated by the repassivation region.     

Determination of p-nitroaniline by the tartrate-acetone-Mn2+-KBrO3-H2SO4 double organic substrate oscillating system using non-equilibrium stationary state

This paper described the determination of p-nitroaniline in a double organic substrate oscillating system of tartrate-acetone-Mn²⁺-KBrO₃-H₂SO₄. Under the optimum conditions, temperature was chosen as a control parameter to design the bifurcation point and proposed a convenient method for determination of p-nitroaniline. Results showed that the system consisting of 3.5 mL 0.06 mol L⁻¹ tartrate, 4.0 mL 0.7 mol L⁻¹ H₂SO₄, 1.5 mL 1.5×10⁻⁴ mol L⁻¹ MnSO₄, 4.0 mL 0.4 mol L⁻¹ acetone and 7.0 mL 0.05 mol L⁻¹ KBrO₃ was very sensitive to the surrounding at 33.5°C. A good linear relationship between the potential difference and the negative logarithm concentration of p-nitroaniline was obtained to be in the range of 2.50×10⁻⁷∼3.75×10⁻⁵ mol L⁻¹ with a lower detection limit of 2.50×10⁻⁸ mol L⁻¹.      

The Thermal Expansion of Wood Cellulose Crystals

We have investigated tension wood cellulose obtained from Populus maximowiczii using X-ray diffraction at temperatures from room temperature to 250 °C. Three equatorial and one meridional d-spacings showed a gradual linear increase with increasing temperature. For temperatures above 180 °C, however, the equatorial d-spacing increased dramatically. Thus, the linear and volume thermal expansion coefficients (TECs) below 180 °C were determined from the d-spacings. The linear TECs of the a-, b-, and c-axes were: α _a = 13.6 × 10⁻⁵ °C⁻¹, α _b = −3.0× 10⁻⁵ °C⁻¹, and α _c =0.6× 10⁻⁵ °C⁻¹, respectively, and the volume TEC was β = 11.1× 10⁻⁵ °C⁻¹. The anisotropic thermal expansion in the three coordinate directions was closely related to the crystal structure of the wood cellulose, and it governed the macroscopic thermal behavior of solid wood.     

Spectrophotometric method for the determination of telmisartan with congo red

In pH 2.50 HCl-NaAc buffer solution, the reaction between telmisartan and congo red could form ionassociation complex, which has the maximum absorbance at 593 nm in the spectrophotometric experiment. Under this wavelength, the Beer’s law was obeyed within the concentration range of 1.08 × 10⁻⁶−2.24 × 10⁻⁵ M. The linear regression equation was A = −0.1913 × 10⁵ c + 0.0286 (C: M). The regression coefficient r was 0.9986. The apparent molar coefficient ɛ₅₉₃ was 1.63 × 10⁴ L mol⁻¹ cm⁻¹ and the detection limit was 5.66 × 10⁻⁷ M. The established method having high sensitivity and good selectivity could be applied to the determination of telmisartan in pharmaceutical, urine and blood plasma samples with satisfactory results. The reaction mechanism was also discussed by using density functional theory methods. The result obtained was consilient with experimental data. The article is published in the original.)     

Photometric determination of aqueous cobalt (II), nickel (II), copper (II) and iron (III) with 1-nitroso-2-naphthol-3,6-disulfonic acid disodium salt in gelatin films

Photometric determination of aqueous Co(II), Cu(II), Ni(II) and Fe(III) was performed using indicator films prepared by immobilization of 1-nitroso-2-naphthol-3,6-disulfonic acid disodium salt (NRS) into hardened photographic film. Immobilization was based on electrostatic interaction of reagent and metal complexes with the gelatin. The isoelectric point pH of hardened gelatin (4.46±0.04) was evaluated by viscometry. Co(II), Fe(III), Ni(II) form 1:3 complexes with NRS in gelatin at pH 2 and Cu(II) forms 1:2 complexes. Their log β′ values were: Co-6.7, Fe-8.6, Cu-8.0, and Ni-6.4. The absorption maxima were: 370nm for NRS, and 430nm, 470nm, 495nm and 720nm for complexes of Co(II), Ni(II), Cu(II) and Fe(III). An algorithm for their simultaneous determination using the indicator films was developed. The detection limits were: c_lim(Co²⁺) = 0.45×10⁻⁵ M, c_lim(Fe³⁺) = 0.50×10⁻⁵ M, c_lim(Cu²⁺) = 0.67×10⁻⁵ M, c_lim(Ni²⁺) = 0.75×10⁻⁵ M,; and their sum c_lim(ΣMn⁺) = 0.82×10⁻⁵ M.      

Chemiluminescence determination of chromium(III) and total chromium in water samples using the periodate-lucigenin reaction

A new chemiluminescence (CL) method combined with flow injection technique is described for the determination of Cr(III) and total Cr. It is found that a strong CL signal is generated from the reaction of Cr(III), lucigenin and KIO₄ in alkaline condition. The determination of total Cr is performed by pre-reduction of Cr(VI) to Cr(III) by using H₂SO₃. The CL intensity is linearly related to the concentration of Cr in the range 4.0 × 10⁻¹⁰–1.0 × 10⁻⁶ g mL⁻¹. The detection limit (3s _b) is 1 × 10⁻¹⁰ g mL⁻¹ Cr and the relative standard deviation is 1.9% (5.0 × 10⁻⁸ g mL⁻¹ of Cr(III) solution, n = 11). The method was applied to the determination of Cr(III) and total Cr in water samples and compared satisfactorily with the official method.     

Flow-injection analysis for the determination of total inorganic carbon and total organic carbon in water using the H2O2–luminol–uranine chemiluminescent reaction

In the presence of carbonate and uranine, the chemiluminescent intensity from the reaction of luminol with hydrogen peroxide was dramatically enhanced in a basic medium. Based on this fact and coupled with the technique of flow-injection analysis, a highly sensitive method was developed for the determination of carbonate with a wide linear range. The method provided the determination of carbonate with a wide linear range of 1.0 × 10⁻¹⁰–5.0 × 10⁻⁶ mol L⁻¹ and a low detection limit (S/N = 3) of carbonate of 1.2 × 10⁻¹¹ mol L⁻¹. The average relative standard deviation for 1.0 × 10⁻⁹–9.0 × 10⁻⁷ mol L⁻¹ of carbonate was 3.7% (n = 11). Combined with the wet oxidation of potassium persulfate, the method was applied to the simultaneous determination of total inorganic carbon (TIC) and total organic carbon (TOC) in water. The linear ranges for TIC and TOC were 1.2 × 10⁻⁶–6.0 × 10⁻² mg L⁻¹ and 0.08–30 mg L⁻¹ carbon, respectively. Recoveries of 97.4–106.4% for TIC and 96.0–98.5% for TOC were obtained by adding 5 or 50 mg L⁻¹ of carbon to the water samples. The relative standard deviations (RSDs) were 2.6–4.8% for TIC and 4.6–6.6% for TOC (n = 5). The mechanism of the chemiluminescent reaction was also explored and a reasonable explanation about chemical energy transfer from luminol to uranine was proposed. Figure Chemiluminescence profiles in batch system. 1, Injection of 100 μL of K₂CO₃ into 1.0 mL luminol-1.0 mL H₂O₂ solution; 2-3 and 4-5, Injection in sequence of 100 μL of K₂CO₃ and 100 μL of uranine into 1.0 ml luminol-1.0 mL H₂O₂ solution; C_luminol = 1.0 × 10⁻⁷ mol/L, C_H2O2 = 1.0 × 10⁻⁵ mol/L, C_uranine = 1.0 × 10⁻⁵ mol/L, C_K2CO3 = 1.0 × 10⁻⁷ mol/L except for 4-5 where C_K2CO3 = 1.0 × 10⁻⁴ mol/L     

Mass Spectrometric Determination of Association Constants of Bovine Serum Albumin (BSA) with para-Sulphonato-Calix[n]arene Derivatives

Electrospray Ionization Mass Spectrometry (ESI/MS) has been used to determine the association constants (K_As) and binding stoichiometries for parent para-Sulphonato-calix[n]arenes and their derivatives with bovine serum albumin (BSA). K_A values were determined by titration experiments using a constant concentration of protein. K_A measurements were carried out in a methanol–formic acid solution. 5,11,17,23–tetra-Sulphonato-calix[4]arene (1a) and 25-mono-(2-aminoethoxy)-5,11,17,23-tetra-Sulphonato-calix[4]arene (1d) interact strongly with BSA showing 3 non-equivalent binding sites with K_A1 = 7.69 × 10⁵ M⁻¹, K_A2 = 3.85 × 10⁵ M⁻¹, K_A3 = 0.33 × 10⁵ M⁻¹ and K_A1 = 1.69 × 10⁵ M⁻¹, K_A2 = 2.94 × 10⁵ M⁻¹, K_A3 = 0.60 × 10⁵ M⁻¹, respectively. The strength of the interactions between the calixarene and BSA is inversely proportional to the size of macrocyclic ring: n = 4 > n=6>>n=8.     

Adsorptive Voltammetric Studies on the Cerium(III)–Alizarin Complexon Complex at a Carbon Paste Electrode

A novel procedure was developed for the determination of trace cerium on the basis of anodic adsorption voltammetry of the Ce(III)–alizarin complexon (ALC) complex at a carbon paste electrode (CPE). The procedure is convenient to determine cerium individually in the presence of other rare earths because there is a 100 mV difference between the peak potentials of Ce(III)–ALC and other rare earth(III)–ALC complexes in a supporting electrolyte of 0.08 M HAc–NaAc and 0.012 M potassium biphthalate (pH 4.7) when performing linear-scanning from −0.2 to 0.8 V (vs. SCE) at 100 mV/s. The second-order derivative peak currents are directly proportional to the Ce(III) concentration over a range of 6.0 × 10⁻⁹–3.0 × 10⁻⁷ M. The detection limit is as low as 2.0 × 10⁻⁹ M (S/N = 3) for a 120 s preconcentration. An RSD of 3.5% was obtained for 15 determinations of Ce(III) at a concentration of 4.0 × 10⁻⁸ M on the same CPE surface. The method was applied successfully to the determination of cerium in samples of rare earth nodular graphite cast iron.     

Iodide ion selective poly(aniline) solid contact electrode based on quinine-cu ionophores

Iodide ion selective poly(aniline) solid contact electrode based on quinine-Cu ionophore as a sensing material has been successfully developed. The electrode exhibits good linear response of 52.0 mV/decade (at 20 ± 0.2°C, r ² = 0.9998) within the concentration range of 1 × 10^−6.4–1 × 10^−1.0 M KI. The composition of this electrode was quinine-Cu 2.0: PVC 30.0: bis(2-ethylhexyl)sebacate 68.0 (mass). This plasticizer provides the best response characteristics. The electrode shows good selectivity for iodide ion in comparison with any other anions and is suitable for use with aqueous solutions of pH 3.3–9.4. The standard deviations of the measured EMF difference were ±1.4 and ±1.3 mV for iodide sample solutions of 1.0 × 10⁻² M and 1.0 × 10⁻³ M, respectively. The stabilization time was less than 10 min and response time was less than 15 sec.     

Investigation of calcium antagonist–L-type calcium channel interactions by a vascular smooth muscle cell membrane chromatography method

The dissociation equilibrium constant (K _D) is an important affinity parameter for studying drug–receptor interactions. A vascular smooth muscle (VSM) cell membrane chromatography (CMC) method was developed for determination of the K _D values for calcium antagonist–L-type calcium channel (L-CC) interactions. VSM cells, by means of primary culture with rat thoracic aortas, were used for preparation of the cell membrane stationary phase in the VSM/CMC model. All measurements were performed with spectrophotometric detection (237 nm) at 37 °C. The K _D values obtained using frontal analysis were 3.36 × 10⁻⁶ M for nifedipine, 1.34 × 10⁻⁶ M for nimodipine, 6.83 × 10⁻⁷ M for nitrendipine, 1.23 × 10⁻⁷ M for nicardipine, 1.09 × 10⁻⁷ M for amlodipine, and 8.51 × 10⁻⁸ M for verapamil. This affinity rank order obtained from the VSM/CMC method had a strong positive correlation with that obtained from radioligand binding assay. The location of the binding region was examined by displacement experiments using nitrendipine as a mobile-phase additive. It was found that verapamil occupied a class of binding sites on L-CCs different from those occupied by nitrendipine. In addition, nicardipine, amlodipine, and nitrendipine had direct competition at a single common binding site. The studies showed that CMC can be applied to the investigation of drug–receptor interactions.     

A quartz crystal microbalance study of β-cyclodextrin self assembly on gold and complexation of immobilized β-cyclodextrin with adamantane derivatives

Quartz crystal microbalance (QCM) was used to study the self-assembly of per-6-thio-β-cyclodextrin (t₇-βCD) on gold surfaces, and the subsequent inclusion interactions of immobilized βCD with adamantane-poly(ethylene glycol) (5,000 MW, AD-PEG), 1-adamantanecarboxylic acid (AD-C) and 1-adamantylamine (AD-A). From a 50 μM solution of t₇-βCD in 60:40 DMSO:H₂O, a t₇-βCD layer was formed on gold with surface density of 71.7 ± 2.7 pmol/cm², corresponding to 80 ± 3% of close-packed monolayer coverage. Gold sensors with immobilized t₇-βCD were then exposed alternately to six different concentrations of AD-PEG, 500 μM AD-C or 500 μM AD-A aqueous solutions for association, and water for dissociation. Association of AD-PEG conformed to a Langmuir isotherm, with a best fit equilibrium constant K = 125,000 ± 18,000 M⁻¹. For AD-C and AD-A, association (k _a ) and dissociation (k _d ) rate constants were extracted from kinetic profiles by fitting to the Langmuir model, and equilibrium constants were calculated. The parameters for AD-C were found to be: k _a = 100 ± 5 M⁻¹ s⁻¹, k _d = 110 (±18) × 10⁻⁴ s⁻¹, and K = 9,400 ± 1,700 M⁻¹. For AD-A, k _a = 58 ± 6 M⁻¹ s⁻¹, k _d = 154 (±7) × 10⁻⁴ s⁻¹, and K = 3,800 ± 400 M⁻¹. The results demonstrate the utility of QCM as a tool for studying small molecule surface adsorption and guest–host interactions on surfaces. More specifically, the kinetic and thermodynamic data of AD-C, AD-A, and AD-PEG inclusion with immobilized t₇-βCD form a basis for further surface association studies of AD-X conjugates to advance surface sensory and coupling applications.     

Determination of levofloxacin hydrochloride with multiwalled carbon nanotubes-polymeric alizarin film modified electrode

Multiwalled carbon nanotubes-polymeric alizarin film modified electrode was made. The electrochemical behavior of levofloxacin hydrochloride on modified electrode was studied with cyclic voltammetry, linear sweep voltammetry and chronopotentiometry. The results indicated that the electrical oxidation of levofloxacin hydrochloride on MWNT-PAR electrode, in HAc-NaAc buffer solution at pH 4.2 was irreversible and was controlled by diffusion. Some important parameters m, n, D, E _D, ΔS _rc and ΔH _rc of the electrochemical process were evaluated. Good linearity relationship between peak current and its concentration in the range of 5.0 × 10⁻⁶–1.0 × 10⁻⁴ mol l⁻¹ was found, of which the equation was I _p(A) = −5.456 × 10⁻⁶ 0.2667c, the correlative coefficient r = −0.9976 and detect limitation was 4.0 × 10⁻⁷ mol l⁻¹. The recovery of levofloxacin hydrochloride in levofloxacin hydrochloride injection was between 94.6 and 104.7%.     

Voltammetric sensor for nitrite determination based on its electrocatalytic reduction at the surface of p-duroquinone modified carbon paste electrode

A p-duroquinone (tetramethyl-p-benzoquinone) modified carbon paste electrode (DMCPE) was employed to study the electrocatalytic reduction of nitrite in aqueous solutions using cyclic voltammetry (CV), double potential-step chronoamperometry, and differential pulse voltammetry (DPV). It has found that under an optimum condition (pH 1.00), the reduction of nitrite at the surface of DMCPE occurs at a potential of about 660 mV less negative than that of an unmodified carbon paste electrode (CPE). The catalytic rate constant, k′_h, based on Andrieux and Saveant theoretical model was calculated as for scan rate 10 mV s^-1. Also, the apparent diffusion coefficient, D _app, was found as 2.5 × 10^–10 and 3.61 × 10^–5 cm² s^-1 for p-duroquinone in carbon paste matrix and nitrite in aqueous buffered solution, respectively. The values for αn_α were estimated to be −0.65 and −0.19 for the reduction of nitrite at the surface of DMCPE and CPE, respectively. The electrocatalytic reduction peak currents showed a linear dependence on the nitrite concentration, and a linear analytical curve was obtained in the ranges of 5.0 × 10^–5 M to 8.0 × 10^–3 M and 6.0 × 10^–6 M to 8.0 × 10^–4 M of nitrite concentration with CV and DPV methods, respectively. The detection limits (2σ) were determined as 2.5 × 10^–5 M and 4.3 × 10^–6 M by CV and DPV methods. This method was also applied as a simple, selective and precise method for determination of nitrite in real samples (the weak liquor from the wood and paper factory of Mazandaran province in Iran) by using a standard addition method.     

Ion-pair formation in the outer-sphere electron transfer reactions between tris-(1, 10) phenanthroline iron(II) and the halopentacyanocobaltate(III) complexes in aqueous acidic solutions

The kinetics of the reactions between Fe(phen) ₃ ²⁺ [phen = tris–(1,10) phenanthroline] and Co(CN)₅X³⁻ (X = Cl, Br or I) have been investigated in aqueous acidic solutions at I = 0.1 mol dm⁻³ (NaCl/HCl). The reactions were carried out at a fixed acid concentration ([H⁺] = 0.01 mol dm⁻³) and the second-order rate constants for the reactions at 25 °C were within the range of (0.151–1.117) dm³ mol⁻¹ s⁻¹. Ion-pair constants K _ip for these reactions, taking into consideration the protonation of the cobalt complexes, were 5.19 × 10⁴, 3.00 × 10² and 4.02 × 10⁴ mol⁻¹ dm⁻³ for X = Cl, Br and I, respectively. Activation parameters measured for these systems were as follows: ΔH* (kJ K⁻¹ mol⁻¹) = 94.3 ± 0.6, 97.3 ± 1.0 and 109.1 ± 0.4; ΔS* (J K⁻¹) = 69.1 ± 1.9, 74.9 ± 3.2 and 112.3 ± 1.3; ΔG* (kJ) = 73.7 ± 0.6, 75.0 ± 1.0 and 75.7 ± 0.4; E _a (kJ) = 96.9 ± 0.3, 99.8 ± 0.4, and 122.9 ± 0.3; A (dm³ mol⁻¹ s⁻¹) = (7.079 ± 0.035) × 10¹⁶, (1.413 ± 0.011) × 10¹⁷, and (9.772 ± 0.027) × 10²⁰ for X = Cl, Br, and I respectively. An outer – sphere mechanism is proposed for all the reactions.     

Determination of pheniramine enantiomers in eye drop by capillary electrophoresis using hydroxypropyl-β-cyclodextrin as chiral selector

A capillary zone electrophoresis procedure has been developed for the chiral determination of pheniramine in eye drop. Native and derivative cyclodextrins (CDs) including γ-CD, β-CD, hydroxypropyl-β-CD and dimethyl-β-CD were tested as chiral selectors. Using 30 mM hydroxypropyl-β-CD in 50 mM phosphate buffer (pH 3.0), the acceptable resolution value (R = 1.55) was obtained. The assay was validated for linearity (3.3 × 10⁻⁶–5.0 × 10⁻⁴ M; R ² = 0.9996), limit of detection (3.3 × 10⁻⁶ M), limit of quantification (8.5 × 10⁻⁶ M), analytical precision by terms of intra- and inter-day variability (RSD ≤ 2.57%), and accuracy (recovery ≥ 89.3%). The content of pheniramine in eye drop obtained by the proposed method was in good agreement with the declared value. The results indicated that pheniramine in the eye drop was present as the racemate.     

Adsorption of Cu(II), Cd(II), Pb(II), Cr(VI) by double hydroxides on the basis of Al oxide and Zr, Sn, and Ti oxides

It was studied the equilibrium adsorption and adsorption kinetics of Cu(II), Cd(II), Pb(II), and Cr(VI) by composite hydroxides formed by Me _x O _y · nH₂O and Me_0.4–0.7Al_0.6–0.3O _y · nH₂O, where Me = Zr, Sn and Ti. It was estimated the values of the diffusion coefficients of adsorbed ions Cu(II) and Cr(VI) from kinetic values. It was established that the estimated diffusion coefficients of adsorbed ions Cu(II) are in the range 0.4 × 10⁻¹²–2.5 × 10⁻¹² m²/s for individual hydroxides and 1.2 × 10⁻¹²–2.8 × 10⁻¹² m²/s for double hydroxides. The obtained values of diffusion coefficients Cr (VI) for double hydroxides are 0.1 × 10⁻¹⁰–0.4 × 10⁻¹⁰ m²/s.     

Electrocatalytic determination of dopamine in pharmaceutical and human serum samples by using [N,N′-bis(2-pyridine carboxamido)-1,2-benzene] nickel(II) modified carbon paste electrode

The main purpose of this study is to develop an inexpensive, simple, selective and especially sensitive modified carbon paste electrode (MCPE) for the determination of dopamine (DA) in pharmaceutical and human serum samples. The carbon paste electrode (CPE) has been modified by using [N,N′-bis(2-pyridine carboxamido)-1,2-benzene] nickel(II) complex (Ni(II)bpb) and the electrochemical behavior of the modified electrode has been studied by cyclic voltammetry. The modified electrode shows an excellent electrocatalytic effect on the oxidation of DA. Under optimum conditions, calibration plots are found to be linear in the range of 7.0 × 10⁻⁷−1.0 × 10⁻⁵ M (r ₂ = 0.9940) and 1.0 × 10⁻⁵−1.0 × 10⁻⁴ M (r₂ = 0.9945); the detection limit is 6.2 × 10⁻⁸ M. The preparation of MCPE is very easy. The electrode can be renewed by simple polishing. The proposed method shows good sensitivity, reproducibility (RSD ∼ 2.9%), high stability (more than two month) without any considerable change in response and recovery for the determination of DA. The prepared electrode has been successfully applied to the voltammetric determination of DA in pharmaceutical and biological samples. The article is published in the original.     

Direct electron transfer of hemoglobin on dihexadecyl hydrogen phosphate/single-wall carbon nanotubes film modified Au electrode and its interaction with taxol

Direct electrochemistry of hemoglobin (Hb) immobilized on the dihexadecyl hydrogen phosphate (DHP)/single-wall carbon nanotubes (SWNTs) film modified Au electrode is investigated. The immobilized Hb displays a couple of stable and well-defined redox peaks, whose formal potential (E ⁰) is −0.434 V (SCE) in a phosphate buffer solution of pH 7.0. The formal potential of the heme Fe(III)/Fe(II) couple shifts negatively linearly with increased pH with a slope of −42.3 mV/pH, denoting that one electron transfer accompanies single proton transportation. Both SWNTs and DHP can accelerate the electron transfer between Hb and the electrode. Using DHP/Hb/SWNTs-film-modified Au electrode, the interaction between Hb and taxol is investigated. The voltammetric response of Hb decreases with increasing concentration of taxol. The peak currents decreases proportionally to the taxol concentration at 1.4 × 10⁻⁵ to 1.3 × 10⁻⁴ M, the linear regression equation being Δi (A) = 2.9603 − 0.4225 c_taxol (M), with a correlation coefficient (r) 0.9985, and the detection limit 6.95 × 10⁻⁶ M (signal-to-noise ratio of three). Published in Russian in Elektrokhimiya, 2007, Vol. 43, No. 7, pp. 801–807. The text was submitted by the authors in English.     

Electrochemical synthesis of poly(<Emphasis Type="Italic">O</Emphasis>-tolidine): Electrochemical and spectroscopic characterization

Polymerization of (O-tolidine), as ring substituted derivative of benzidine was achieved electro-chemically in organic solution containing Bu₄NBF₄ (0.2 M) in dichloromethane as supporting electrolyte. The film was obtained by electropolymerization in solution containing monomer in various ratio ((5 × 10⁻⁴)–(5 × 10⁻²) M). This polymer was characterized by cycling voltammetry, impedance measurement, UV-visible and FT-IR spectroscopy.