Determination of Trace Germanium in Plants by Graphite Furnace Atomic Absorption Spectrometry With Methyl Iso-butyl Ketone and N,N-Dimethylformamide Extraction
Bao Changli, Cheng Xinliang, Liu Chunhua(Department of Geochemical Rock Surveys, Changchun University of Earth Science, Changchun 130026) Wei Yongdi(Bethune University of Medical Sciences)
The optimal conditions for the determination of germanium were studied by gra phite furnace atomic absorption spectrometry using graphite tube impregnated and treated with ammonium molybdate. The experimental results show that chelates of germanium and phenylfluorone could be extracted by methyl iso-buthyl ketone and dissolved by N,N-dimethylformamide. Using ammonium hydroxide as a matrix modifier, the sensitivity of germanium was 20 times as high as that in graphite furnace one. The method was used to determine trace germanium in Ginseng and other plants directly.The sensitivity (1％A), detection limit, relaive standard deviation and recovery were 1.07×10~(-11), 2.20× 10~(-10)g, 3.4％～7.6％ and 97％～103％, respectively.