微波消解试样-火焰原子吸收光谱法测定蛋白粉中铜和钙
FAAS Determination of Copper and Calcium in Protein Powder with Microwave Assisted Sample Digestion
-
摘要: 蛋白粉试样经硝酸于高温(180 ℃)高压(3.0 MPa)下微波密闭消解,用火焰原子吸收光谱法测定了蛋白粉中铜和钙的含量.对仪器工作条件作了详述,选择波长为324.75,422.7 nm谱线依次作为测定铜和钙的分析线.试样结果表明:与干灰化法相比较,微波消解法处理样品所得结果的准确度和精密度更好.应用此法测定了蛋白粉中铜和钙的含量,铜和钙的标准加入回收率分别为100.5%和99.4%,相对标准偏差(n=7)均小于1.0%.Abstract: Sample of protein powder was digested with HNO3 in a closed vessel,heated at 180 ℃and under a pressure of 3.0 MPa by using microwave sample digestor.The solution obtained was used for FAAS determination of Cu and Ca.The working conditions of the instrument were described in detail,and wavelengths of 324.75,422.7 nm were selected as analytical spectral lines for the determination of Cu and Ca respectively.It was found that precision of results obtained by microwave assisted sample digestion method was better than those obtained by the dry ashing method.The proposed method was used in the determination of contents of Cu and Ca in protein powder.Values of recovery of Cu and Ca found by standard addition method were 100.5% and 99.4% respectively with values of RSD′s (n=7) less than 1.0%.