Zhang Yuan, Luo Wen-hong, Li Hui
Shantou University Medical College Central Laboratory, Shantou 515041, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2005 Apr;25(4):576-8.
In buffer solution of citric acid monohydrate-disodium hydrogen phosphate at pH 5-7.5, cobalt water samples were chelated by 1-(2-pyridylazo)-2-naphthol (PAN) to form Co-PAN. After water-bath at 66 degrees C for two hours, Co-PAN is extracted into Triton X-100 nonionic surfactant phase and separated from bulk water. Extracted cobalt content was measured by graphite furnace atomic absorption spectrometry. The surfactant phase separated was treated with 0.5% HNO3-0.1% Pd(NO3)2 to remove background interference at 1200 degrees C temperature. The pre-concentration of cobalt in water samples permitted the detection of 0.003 microg x L(-1) (10sigma) with the enhancement factor of 100. The recoveries were 90.5%-106%. The proposed method was applied to the determination of cobalt in water samples and satisfactory results were obtained.
在pH值为5 - 7.5的柠檬酸一水合物 - 磷酸氢二钠缓冲溶液中，钴水样用1 -（2 - 吡啶偶氮）- 2 - 萘酚（PAN）螯合形成Co - PAN。在66℃水浴两小时后，Co - PAN被萃取到Triton X - 100非离子表面活性剂相中并与大量水分离。通过石墨炉原子吸收光谱法测定萃取的钴含量。分离出的表面活性剂相用0.5% HNO₃ - 0.1% Pd(NO₃)₂处理，以在1200℃温度下去除背景干扰。水样中钴的预富集使得能够检测到0.003 μg·L⁻¹（10σ），增强因子为100。回收率为90.5% - 106%。该方法应用于水样中钴的测定，获得了满意的结果。
