| Autor: |
Placido Torres, Daiane, Antunes Vieira, Mariana, Schwingel Ribeiro, Anderson, Curtius, Adilson José |
| Zdroj: |
JAAS (Journal of Analytical Atomic Spectrometry); 2005, Vol. 20 Issue: 4 p289-294, 6p |
| Abstrakt: |
A very simple procedure is proposed for the determination of total and inorganic Hg in biological materials. Organic Hg methylmercury can be obtained from the difference. After treating the sample at room temperature with tetramethylammonium hydroxide TMAH, inorganic Hg is obtained by cold vapor atomic absorption spectrometry CV-AAS, keeping the quartz cell at room temperature, while total Hg is obtained by the same technique, heating the quartz cell in an air–acetylene flame. By analyzing several biological certified materials, it was evident that the difference between the mentioned concentrations corresponds to methylmercury. Cold vapor graphite furnace atomic absorption spectrometry CV-GF-AAS with retention of the vapor in a heated Au-treated graphite tube was used to optimize the vapor generation conditions and also to determine total Hg. In a general way, the concentrations obtained by both techniques were in agreement with the certified values or with differences of the certified values for total, Hg2and CH3Hg, according to the t-test for a 95 confidence level. Total Hg results obtained by the two techniques were also in agreement. The relative standard deviations were lower than 10 for most of the results. The detection limits in the sample were: 0.13 μg g−1for total Hg and 0.025 μg g−1for Hg2by CV-AAS. The detection limit for total Hg by CV-GF-AAS was 0.001 μg g−1. It is amazing how this very simple method is able to provide very important information on mercury speciation. |
| Databáze: |
Supplemental Index |
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