A precise determination of the complex mechanism of catalysis and inhibition involved in the reaction of HRP with H(2)O(2) as substrate and an outersphere single electron donor ([Os(bpy)(2)pyCl](+)) as cosubstrate is made possible by a systematic analysis of the cyclic voltammetric responses as a function of the scan rate and of the substrate and cosubstrate concentrations, complemented by spec...

A kinetic method developed for the determination of ultra-trace amounts of nitrite based on its catalytic effect on the reaction between potassium bromate and Nile blue A in strongly acidic media is reported. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of Nile blue A at 645 nm by the fixed-time method. The decrease in absorbance during the first...

Zero, first and second order derivative spectrophotometric methods were developed for the determination of insulin. The standard solutions and pharmaceutical sample were prepared in 0.01 M HCl. Absorbences of insulin were measured at 276 nm for the zero order by measuring height of peak from zero, at 264, 277 and 284 nm for the first order and at 277, 280, 283 and 289 nm for second order deriva...