Abstrato

Determination of gold by electrothermal atomic absorption spectrometry after single drop microextraction

Saeid Nazari

Due to the importance of gold and their extremely lowlevels variousmatrices, highly sensitive and rapid methods required for its trace and ultra trace determination. In trace element analysis, preconcentration and separation methods enhance the sensitivity and precision of the determination. In this work we describe a high sensitive method for extraction and determination of gold in aqueous samples by liquid phase microextracion combined with a graphite furnace atomic absorption spectrometry. For obtaining higher sensitivity we applied method of “single drop microextraction” for determination of trace amounts of gold. In thismethod Au is reactedwithOrthophenylen 2-mercapto aniline, the complex formed was then extracted into micro drop of 1,2 dichloroethane.After extraction, the micro drop was retracted and directly transferred into a graphite tube modified by [Pd(c)+Pd(i)]. The detection limit was calculated to be 0.8g/l (absolute value of 0.3 ng) based on 3Sb. The relative standard deviation for five replicate analysis of 10g/l Au was 6.5%. The calibration curve was linear in the range of 0.8 to 40g/l with a sensitivity of 0.25g/l.