Spectrophotometric determination of Nano amounts of gallium (III)‎ using 2-(5-bromo-2-pyridylazo)‎-5-diethylaminophenol reagent in water samples

Abstract EN

The aim of the present work is to develop a simple and sensitive spectrophotometric method for determination of nano amounts of Ga(III) using 2-(5-Bromo-2-Pyridylazo)-5-Diethylaminophenol (5-Br-PADAP) reagent.

The factors affecting the determination procedure including absorption spectra, pH value, surfactant type and dye reagent concentration were studied and optimized.

Interferences had also been evaluated.

Maximum absorbance was obtained at 573 nm at pH 2.75, after 5 minutes mixing time.

The proposed method was valid for Ga(III) concentration determination ranging from 0.005 to1.25 μg ml-1 in aqueous solution.

However, the detection limit was decreased up to 0.001 μg ml-1 in the presence of methanol.

The ratio between Ga(III) and 5-Br-PADAP was found to be 1:1 with apparent molar absorptivity 1.12 × 105 l mol-1cm-1 and coefficient of variation 0.44%.

The elucidation of the complex composition was proved using FTIR technique.

The method was applied for the determination of Ga(III) in some polluted water samples from different sources.