ICP-AES法同时测定水牛奶中钙、镁、磷、铁和锌

Determination of calcium,magnesium,phosphorus,iron,and zinc in buffalo milk by inductively coupled plasma-atomic emission spectrometry(ICP-AES)

目的建立用微波消解、电感耦合等离子体发射光谱法同时测定水牛奶中的钙、镁、磷、铁和锌的方法。方法采用硝酸、过氧化氢作溶剂,用微波方法消解水牛奶样品,样液定容后,采用电感耦合等离子体发射光谱法测定水牛奶试液中钙、镁、磷、铁和锌。测定时选择波长为317.993nm{106}、202.582nm{466}、178.284nm{489}、238.204nm{141}和213.856nm{457}光谱线分别作为Ca、Mg、P、Fe、Zn分析线。结果钙、镁、磷、铁、锌检出限分别为0.091、0.063、0.037、0.019、0.012mg/kg,加标回收率为94.7%～108.2%,相对标准偏差(RSD,n=11)均小于2.5%。结论本方法分析结果与国标方法测定值相符,具有重复性好、消解用试剂量少、操作简单、检测速度快、多元素同时测定、减少环境污染等优点。

Objective To establish a method for determination of calcium, magnesium, phosphorus, iron and zinc in buffalo milk by inductively coupled plasma-atomic emission spectrometry(ICP-AES) with micro-wave sample digestion. Methods The buffalo milk samples were dissolved by microwave digestion using ni-tric acid and hydrogen peroxide as solvent and determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The spectral lines for Ca, Mg, P, Fe and Zn were 317.993 nm{106}, 202.582 nm{466}, 178.284 nm{489}, 238.204 nm{141} and 213.856 nm{457}. Results The detection limit of Ca, Mg, P, Fe and Zn were 0.091, 0.063, 0.037, 0.019 mg/kg and 0.012 mg/kg. The recoveries for these elements were 94.7%～108.2%with relative standard deviation(RSD, n=11) less than 2.5%. Conclusion The analytical results consisted with those obtained by national standard method. This method has many advantages, such as good repeatability, less use of digestion reagent, easy operation, synchronous determination of multiple ele-ments, fast testing velocity, and less pollution.