The electrochemical oxidation of iodide ion in the presence of 4-hydroxycoumarin (1) was studied using cyclic voltammetry and controlled-potential coulometry. The result indicates that the resulting iodine takes part in a halogenation reaction and reacts with 4-hydroxycoumarin (1). According to the obtained results, a new and simple coulometric titration method with potentiometric end-point det...

The possibilities of application of iodine as a titrant in determination of sulfur compounds have been presented. The influence of the reaction medium, the nature of compounds, and the thiol–thione tautomerism on the reaction stoichiometry of sulfur compounds with iodine has been discussed. The conditions of volumetric titration with visual and potentiometric end-point detection and coulometric...

A potentiometric aspartame biosensor was fabricated by simply depositing the carboxylesterase (CES)-bonded poly(n-butyl acrylate-n-acryloxysuccimide) [CES-poly(nBA-NAS)] microspheres on a Ag/AgCl screen-printed pH selective electrode. The transducer made from non-plasticized polyacrylate membrane containing hydrogen ionophore and lipophilic salt. immobilized CES enzyme catalyzed enzymatic hydro...

Construction and characterization of potentiometric membrane sensors for quantification of diclofenac and warfarin drugs are described. The membranes of the sensors incorporate 1.8 wt.% iron(II)-phthalocyanine (Pc) as a molecular recognition reagent, 64.3 wt.% dibutylsebacate (DBS) solvent mediator, 1.8 wt.% tridodecylmethylammonium chloride (TDMAC) as membrane additive and 32.1 wt.% poly(vinyl...

The construction and performance characteristics of new sensitive and selective in situ modified screen printed (ISPE) and carbon paste (ICPE) electrodes for determination of naphazoline hydrochloride (NPZ-HCl) have been developed. The electrodes under investigation show potentiometric response for NPZ-HCl in the concentration range from 7.0×10-7 to 1.0×10-2 M at 25 °C and the electrode respons...

Polymeric membrane ion-selective electrodes (ISEs) have become attractive tools for trace-level environmental and biological measurements. However, applications of such ISEs are often limited to measurements with low levels of electrolyte background. This paper describes an asymmetric membrane rotating ISE configuration for trace-level potentiometric detection with a high-interfering background...

Three simple methods using visual titrimetric, potentiometric and spectrophotometric techniques are described for the determination of acyclovir in pure form and in pharmaceutical formulations. The methods are based on the neutralisation reaction involving the primary amino group of the drug and acetous perchloric acid in acetic acid medium. In titrimetric methods, the titration is completed wi...

The ionophore 1,4,7,10,13-penta(n-octyl)-1,4,7,10,13-pentaazacyclopentadecane (L) was used for the development of miniaturised perchlorate-selective electrodes in thickfilm technology. Different PVC membranes containing L and the plasticizers o-nitrophenyl octyl ether (NPOE), dibutyl phthalate (DBP), bis(2-ethylhexyl)sebacate (DOS) and dibutyl sebacate (DBS) were prepared and placed on a graphi...