Classifications, properties, recent synthesis and applications of azo dyes.

Electrochemical reaction mechanism and determination of Sudan I at a multi wall carbon nanotubes modified glassy carbon electrode

Voltammetric measurements of aminosalicylate drugs using bismuth film electrode

An electrochemical sensor for sulfasalazine determination based on molecularly imprinted polymer (MIP) as recognition element has been developed. A sulfasalazine selective MIP and a non-imprinted polymer (NIP) were synthesized and then incorporated in the carbon paste to prepare the modified carbon paste electrodes. Trace amount of sulfasalazine was determined by using differential pulse voltammetry method based on electrochemical reduction of sulfasalazine at the modified electrodes. The MIP based sensor showed high recognition ability of sulfasalazine in comparison with the NIP based sensor. The influence of experimental parameters affecting sensor response such as carbon paste composition, pH, incubation time, potential scan rate and potential amplitude were optimized. Under optimal conditions, the MIP based sensor exhibited good performance for sulfasalazine over the concentration range of 1.0 × 10 −8 to 1.0 × 10 −6  mol L −1 with a detection limit of 4.6 × 10 −9  mol L −1 and sensitivity 1.11 × 10 7  μA L mol −1 . The MIP based sensor was successfully applied to the determination of sulfasalazine in a commercial pharmaceutical formulation and human serum, offering feasibility and applicability of the sensor to the complex matrices.

Electroanalytical determination of sulfasalazine in pharmaceutical and biological samples using molecularly imprinted polymer modified carbon paste electrode

Application of bismuth-film electrode for cathodic electroanalytical determination of sulfadiazine

Polarographic and voltammetric determination of triazine-based reactive azo dyes with 4-carboxypyridyl and 1,4-diazabicyclo[2,2,2]octanyl (DABCO) leaving groups

Cathodic stripping voltammetry of 2,3-dichloroquinoxaline and 1,4-dichlorophthalazine reactive dyes and their hydrolysis products: Reactive Red 41 and Reactive Red 96

Sulfonamides that form stable metal complexes can be accumulated at a hanging mercury drop electrode in the presence of copper(II). In this preliminary study sulfadimidine, sulfathiazole, sulfamerazine, sulfadiazine and sulfapyridine, which have an ortho heterocyclic nitrogen atom on the ring attached to the sulfonamide nitrogen atom, and which are known to form stable complexes with copper(II), have been accumulated in this way and have been determined indirectly by reduction of the complexed copper to copper amalgam. Sulfanilamide, sulfaguanidine and sulfacetamide, which do not form stable complexes, are not accumulated. Preliminary results indicate that the sulfonamides are accumulated as their copper(I) complexes

Cathodic stripping voltammetric determination of sulfonamides as copper(I) complexes at a hanging mercury drop electrode

Non-reducible organic compounds that can be accumulated at a hanging mercury drop electrode as copper(I) complexes or salts, and can then be determined indirectly by reduction of the copper(I), may interfere in the determination of reducible compounds that adsorb on the electrode and are determined directly by cathodic stripping voltammetry. This would occur if there were appreciable amounts of copper(II) in the sample or in the de-ionized water supply. The prevention of this interference by the use of ethylenediaminetetraacetic acid as the pH buffer is illustrated here in determining sulfasalazine, a sulfonamide drug which has a reducible azo group, in the presence of significantly larger amounts of sulfadimidine (which is not reducible) and copper ion. In this type of application the EDTA serves a dual purpose as the pH buffer and as a complexant to mask interfering cations, such as copper(II).

Use of ethylenediaminetetraacetic acid as a pH buffer to prevent copper(II) interference by complexation in the cathodic stripping voltammetric determination of reducible organic compounds at a hanging mercury drop electrode: Determination of sulfasalazine in the presence of sulfadimidine

A. Rahim H. M. Yusoff

Papers

Polarographic and voltammetric determination of triazine-based reactive azo dyes with 4-carboxypyridyl and 1,4-diazabicyclo[2,2,2]octanyl (DABCO) leaving groups

Cathodic stripping voltammetry of 2,3-dichloroquinoxaline and 1,4-dichlorophthalazine reactive dyes and their hydrolysis products: Reactive Red 41 and Reactive Red 96

Cathodic stripping voltammetric determination of sulfonamides as copper(I) complexes at a hanging mercury drop electrode

Use of ethylenediaminetetraacetic acid as a pH buffer to prevent copper(II) interference by complexation in the cathodic stripping voltammetric determination of reducible organic compounds at a hanging mercury drop electrode: Determination of sulfasalazine in the presence of sulfadimidine