摘要
目的 :探讨不同消化方法及条件对牛奶中钙、锌含量测定的影响 ,确定最佳测定条件。方法 :分别对牛奶样品进行干式灰化及湿式消化 ,用原子吸收分光光度法测定其钙、锌含量。结果 :测牛奶中钙含量选用干式灰化法和湿式消化法处理样品对测定结果无显著影响 (P >0 0 5 ) ,两种方法的回收率、精密度均符合实验要求 ;测牛奶中锌含量选用湿式消化法测得的回收率 (96 1% )明显高于干式灰化法 (88 3% )。结论 :测牛奶中钙含量选用干式灰化法和湿式消化法均可 ,干式灰化法宜选用 5 5 0℃ 4h消化 ,稀释液选择含La3 + 2 %的盐酸溶液 (1%HCl) ;测锌选用湿式消化法较好 ,以 1%HCl溶液做稀释液 ;湿式消化法的消化液宜选用 5∶1HNO3-HClO4混合酸。
Objective To discuss different digestions and conditions made effect on the measurement of Calcium and Zinc content in the milk and then to determine the best measurement.Methods:To make each milk sample dry ashed and wet digested first and then measure the Calcium and Zinc content by using the atomic absorption spectrophotometry. Results Use dry ashing and wet digestion to measure the Calcium content in the milk sample and there is no clear effect made on it (P>0.05); the recovery and precision of these two methods are both up to the requirement; use wet digestion to measure the Zinc content in the milk sample and the recovery (96.1%)of it is apparently higher than that of dry ashing(88.3%). Conclusion:It is alright to choose both dry ashing and wet digestion to measure the Calcium content in the milk samples; it is better to digest by using dry ashing at 550℃ and for 4 hours; the selection of diluent is La 3+ 2% of HCl; it is better to use wet digestion to measure Zinc content and choose 1% HCl as the diluent; it is better to select the mixture of 5∶1 HNO 3-HClO 4 as the diluent of wet digestion.
出处
《微量元素与健康研究》
CAS
2003年第6期48-51,共4页
Studies of Trace Elements and Health
