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[Determination of stannum in urine by graphite furnace atomic absorption spectrometry].

OBJECTIVE
To establish the method of graphite furnace atomic absorption spectrometry for the measurement of stannum in urine with calcium nitrate as the matrix modifier.


METHODS
Graphite tube was pretreated with calcium nitrate as the matrix modifier, the urine sample was diluted with 1% nitric acid and then direct injection was performed for these samples, and graphite furnace atomic absorption spectrometry was applied for measurement.


RESULTS
The concentration of stannum in urine showed a good linear relationship within the range of 8.0~40.0 μg/L, with a correlation coefficient of 0.9981. The minimum detectable concentration was 0.72 μg/L, the degree of precision was 1.54%~6.69%, and the recovery rate was 99.23%~107.63%.


CONCLUSION
This method can determine the content of stannum in urine accurately and rapidly, with a high sensitivity and a low cost.