微波消解石墨炉原子吸收光谱法测定氢化棉籽油中痕量镍

Determination of Trace Nickel in Hydrogenated Cottonseed Oil by Microwave Digestion and Graphite Furnace Atomic Absorption Spectrometry

建立了微波消解样品、塞曼扣背景石墨炉原子吸收测定氢化棉籽油中痕量镍的方法。向0．0500g氢化棉籽油样品中加入2mL的硝酸和0．5mL双氧水，于微波消解仪中消解，用石墨炉原子吸收法测定样品溶液中镍的含量。镍的含量在0．1～50ng／mL范围内与其吸光度呈良好的线性关系，线性相关系数为0．9982，检出限为15pg／mL。测定结果的相对标准偏差为2．33％（n=11），样品加标回收率为94％～102％，该方法的测定结果与美国药典法基本一致。该方法样品处理方法快速、简单，背景空白低，测定结果准确、可靠，适合于实际样品分析。

A method for determination of trace nickel in hydrogenated cottonseed oil by using microwave digestion and graphite furnace atomic absorption spectrometry （GFAAS） was developed. 0.050 0 g hydrogenated cottonseed oil was added with 2 mL nitric acid and 0.5 mL hydrogen peroxide, and then decomposed by microwave digestion. The concentration of nickel in the gotten sample solution was detected by graphite furnace atomic absorption spectrometry. The linear range of nickel content was from 0.1 to 50 ng/mL with the linear correlation coefficient of 0.998 2. The detection limit of nickle was 15 pg/mL, and the relative standard deviation was 2.33%（n =11） with the recoveries of 94% to 102%. The result of the real samples by this method was consistent with that by USP method. The proposed sample preparation method is rapid, simple and has low background and high accuracy. It is reliable and practical in the actual sample analysis.