The Study And Application Of Microsample Introduction-derivative Flame Atomic Absorption Spectrometry For Environmental Samples

Objective: Trace elements play an important role in human metabolism. Either an excess or a deficiency of certain elements in the organism can lead to biological disorder. There are several techniques available to the determination of trace elements including flame atomic absorption spectrometry. But the sensitivity, detection limit and recovery range of which were unsatisfying and it need much sample apply to determination. Researchers have done lots of works to reduce sampling volume, improve the sensitivity further and decrease the interference of flame atomic absorption spectrometry. A new method for the determination of copper, iron and zinc in environmental samples by microsample introduction-derivative flame atomic absorption spectrometry with higher sensitivity and smaller sample quantity was investigated. The optimum conditions concerning the sensitivity were studied.Method: This paper consists of three parts according to different sample. In the first part, the method is described for determining directly trace copper, iron and zinc in relish. In the second part, a sensible, precision and conventionalmethod was proposed for determining copper, iron and zinc in tapwater by microsample introduction-derivative flame atomic absorption spectrometry combining ion exchanging. In the third part, a new method is investigated for determining copper, iron and zinc in flour, maize flour and Chinese herb respectively by microsample introduction-derivative flame atomic absorption spectrometry combining suspension sampling technique.Results: The sensitivity and detection limit of microsample introduction-derivative flame atomic absorption spectrometry were improved greatly. The sensitivity of determining directly trace copper, iron and zinc in relish by microsample introduction-derivative flame atomic absorption spectrometry were 0.011, 0.014 and 0.0053 u g/ml, respectively. The sensitivity of determining trace copper, iron and zinc in tapwater by microsample introduction-derivative flame atomic absorption spectrometry combining ion exchanging were 0.296, 0.595 and 0.065 u g/L, respectively. The sensitivity of determining trace copper, iron and zinc in flour, maize flour and Chinese herb by microsample introduction-derivative flame atomic absorption spectrometry combining suspension sampling were 0.0054, 0.0072 and 0.0027u g/ml, respectively. They were about 30-100 times higher than those of conventional flame atomic absorption spectrometry. The detection limit is improved 10 times and the recovery range of the method is 90-110%.Conclusion: Compared with conventional flame method, the microsample introduction-derivative flame atomic absorption spectrometry for the determination of copper, iron and zinc in environmental samples is sensitive, accurate, precise, simple and rapid. It suit to the determination of copper, iron and zinc in environmental samples...