Analytical Procedure for the Accurate Determination of Ag, Cu and Ni in a Phosphate Buffered Saline Solution Using GF-AAS

作者：Hirano Yuma; Ohshima Yuki; Komata Masashi; Ohtsu Naofumi^*

来源：Bunseki Kagaku, 2016, 65(8): 457-463.

DOI：10.2116/bunsekikagaku.65.457

• graphite furnace atomic absorption spectrometry (GF-AAS)
• antibacterial metals
• phosphate buffered saline (PBS) solution
• calibration curve
• limit of quantification (LOQ).

To obtain accurate quantitative analytical results of Ag, Cu, and Ni in phosphate buffered saline (PBS) solutions by using graphite furnace atomic absorption spectrometry (GF-AAS), the effect of the PBS solution on the linear dynamic range and sensitivity were investigated in detail. For this purpose, the calibration curves of these metals in nitric acid (HNO3) and PBS solutions were constructed using both pyro-coated and uncoated graphite tubes. In the case of Ag, the sensitivity in the PBS with the pyro-coated tube was reduced by ca. 30 % against the HNO3 case, whereas such a reduction was not observed when using an uncoated tube. In the case of Cu, the sensitivity in the PBS was lower than that in the HNO3, regardless of the tube types. In the case of Ni, in contrast, a decrease in the sensitivity was hardly observed in both tubes. To determine the Ag, Cu and Ni concentrations exceeding their linear dynamic ranges, a sample solution should be measured after being diluted adequately. However, in the case of Ag in PBS, Ag chloride precipitates generated in the concentration range exceeding 400 lowered the analytical precision. Similarly, in the case of Cu in PBS, reductions of the accuracy and precision caused by the formation of Cu hydroxide precipitates were observed in the concentration range from approximately 200 to 500 mu g L-1. Analysts should pay attention to the linear dynamic range and the sensitivity of GF-AAS in the quantitative analysis of Ag, Cu and Ni in a PBS. In addition, when analyzing these metals being out of the dynamic range, the solution should be diluted without the formation of precipitates and, otherwise, should be measured after decomposing the precipitates by a pretreatment.

• 出版日期2016-8