In the present study, a novel catalytic-kinetic spectrophotometric method was developed for the determination of trace amounts of copper. It is based on the catalytic effect of Cu(II) on the reduction of brilliant cresyl blue (BCB) by ascorbic acid in pH 5.0 acetate buffer medium. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of BCB at 624 nm. The ope...

A simple and sensitive kinetic spectrophotometric method was developed for the determination of isoxsuprine in pharmaceutical preparations. The method is based upon a kinetic investigation of the coupling reaction between isoxsuprine HCl and 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) in borate buffer of pH 7.8 for a fixed time of 30 min. The absorbance of the yellow coloured product was m...

A simple and sensitive kinetic spectrophotometric method for the determination of trace amounts of cerium (IV), based on the catalytic effect of Ce (IV) on the oxidation of Nile blue (NB) by potassium periodate is described. The reaction rate was monitored spectrophotometrically by measuring the decrease in absorbance of NB at 636 nm. The detection limit of the method was 0.15 g ml and the line...

A simple and sensitive kinetic spectrophotometric method has been developed. The method is based on the reduction of Fe(III) with captopril. Fe(II) then reacts with potassium ferricyanide, resulting in the formation of a blue product. The reaction is followed spectrophotometrically by measuring the rate of change of absorbance at 730 nm. Thus, 1.23 x 10(-3) mol L(-1) FeCl3 and 3.04 x 10(-4) mol...

a simple, selective and sensitive method for the determination of trace amount of titanium (iv) based on its catalytic effect on methylene blue- ascorbic acid redox reaction has been reported. the reaction was followed spectrophotometrically by measuring the change in absorbance of methylene blue at 665 nm, 5 minutes after the initiation of the reaction. in this study experimental parameters we...

in this study, a new reaction system for quantitative determination of ascorbic acid was introduced. the developed method is based on inhibitory effect of ascorbic acid on the orange g-bromate system. the change in absorbance was followed spectrophotometrically at 478 nm. the dependence of sensitivity on the reaction variables including reagents concentration, temperature and time was investiga...

The composite diazotization coupling reaction of sulfanilic acid and N, Ndimethylaniline was used for the precise, accurate, and rapid determination of trace amounts of nitrite ion (0.02-3 µg/ml). The reaction was monitored spectrophotometrically by measuring the absorbance of the produced methyl orange at 510 nm by a fixed the method of 5.0 minutes. The relative standard deviation for the...

A kinetic spectrophotometric method for rapid measurement of thiocyanate in serum, urine and sewage water with no need for removed of interfering substances in described. The method is based on the inhibitory effect of thiocyanate on the oxidation of pyrogallol red by bromated and nitrite which is monitored at 467 nm. The variables affecting the rate of the reaction were investigated and th...

In this study, a new reaction system for quantitative determination of ascorbic acid was introduced. The developed method is based on inhibitory effect of ascorbic acid on the Orange G-bromate system. The change in absorbance was followed spectrophotometrically at 478 nm. The dependence of sensitivity on the reaction variables including reagents concentration, temperature and time was investiga...

A simple and sensitive extraction-spectrophotometric method for rapid and accurate determination of benzocaine in pure and dosage forms was developed. Benzocaine was effectively extracted as a 1:1 ion pair complex with dicyclohexyl-18-crown-6 and calmagite in acidic media into chloroform, followed by spectrophotometric determination at 486 nm. Molar absorptivity of the ternary complex at this w...