An atomic absorption spectrometric method for the determination of trace amounts of zinc after adsorption of its [1-(2-pyridylazo)-2-naphthol] complex on microcrystalline naphthalene has been developed. This complex is adsorbed on microcrystalline naphthalene in the pH range 3.5-7.5 from large volumes of aqueous solutions of various alloys and biological samples with a preconcentration factor o...

This colorimetric method for determination of zinc in seminal liquid is based on the reaction between zinc and 4-(2-pyridylazo)resorcinol in a buffered solution at pH 9.5. It is very simple, fast (approximately equal to 10 min), and economical. It can be used to determine zinc in "whole" semen, seminal plasma, or isolated spermatozoa. We verified its accuracy for sample concentrations up to 0.4...

The redox potentials of cobalt and iron complexes with ten pyridylazo compounds, E(0)(ML2) (ML(2)(+/0); M: Co(III/II), Fe(III/II); L(-): pyridylazo compounds), have been determined in order to explore the difference in their reversed-phase HPLC behavior. The redox potentials of Co complexes were in the range of -0.62 - 0.03 V, while those of Fe complexes were -0.06 - 0.59 V relative to 0.20 V f...

A highly selective, sensitive, rapid and economical differential pulse polarographic method has been developed for the determination of trace amounts of cadmium in various samples after the adsorption of its 1-(2-pyridylazo)-2-naphthol (PAN) complex on microcrystalline naphthalene in the pH range of 8.2-11.0. After filtration, the solid mass is shaken with 9.0 mL of 1 M hydrochloric acid and ca...

We show how zinc may easily be quantified in serum by first using an optimum concentration of guanidine hydrochloride to cause release of zinc from proteins, followed by complexation of released metals with cyanide. The cyanide complex of zinc is preferentially demasked with chloral hydrate, followed by a colorimetric reaction between zinc and 4-(2-pyridylazo)resorcinol. This is a sensitive wat...

A new kinetic spectrophotometic method for the determination of trace amount Chromium (III) in Teareal samples has been described based on it s the catalytic effect on the oxidations of 1 - ( 2 –PyridylAzo ) - 2 - Naphthol, (PAN), by potassium bromated in sulfuric acid. The reaction is followedspec- trophotometrically by measuring the decrease in the absorbance at 469 nm. Under the optimumcondi...

A highly Co (II) liquid ion-selective electrode depending on the reaction of cobalt ions with reagent 2-(5-Bromo-2-pyridylazo)-5-[N-n-propyl-N-(3-sulfopropyl) amino] aniline is successfully fabricated. The characteristic slope (56.66 mV), linear range response from 3.4 × 10−8 to 2.4 10−2 molar, detection limit (2.7 10−8) selectivity coefficient toward some metal ions, time (10 s), lifetime (sev...

a new kinetic spectrophotometic method for the determination of trace amount chromium (iii) in teareal samples has been described based on it s the catalytic effect on the oxidations of 1 - ( 2 –pyridylazo ) - 2 - naphthol, (pan), by potassium bromated in sulfuric acid. the reaction is followedspec- trophotometrically by measuring the decrease in the absorbance at 469 nm. under the optimumcondi...