GFAAS Determination of Ag in Geological Samples with Novel Dispersive Liquid Liquid Microextraction

GFAAS was applied to the determination of Ag in geological samples with novel dispersive liquid liquid microextraction using octanol as extractant. The optimized conditions found were as follows:① amount of octanol (extraction solvent) was 0.30 mL; ② amount of 2 g·L^-1 DPTU (complexing agent) ethanol solution was 1.0 mL; ③ amount of ethanol (dispersant) was 10 mL; ④ pH of sample solution was 3.0-7.0; ⑤ ashing temperature was 500℃; ⑥ atomization temperature was 1 700℃. Linear relationship between values of absorbance and mass concentration of Ag was kept in the range of 0.02-0.50 μg·L^-1, with detection limit (3s) of 4.7 pg. The proposed method was applied to the analysis of geological samples, giving results in consistency with the certified values with RSD's (n=5) in the range of 3.2%-6.8%.