微波消解-分光光度法测定乳清蛋白营养强化粉中磷的含量

Determination of phosphorus in whey protein fortified powder by microwave digestion-spectrophotometry

中文关键词:  磷  乳清蛋白  营养强化粉  微波消解法  分光光度法

英文关键词:phosphorus  whey protein  nutritionally fortified powder  microwave digestion  spectrophotometry

中文摘要:

      目的 建立微波消解-分光光度法测定乳清蛋白营养强化粉中磷含量的测定方法。方法 乳清蛋白营养强化粉中加入硝酸于石墨消解仪中预消解, 待冷却后加入30%过氧化氢使用微波消解仪消解, 样品经过赶酸, 转移至容量瓶中并定容至刻度, 在稀释液中加入钒钼酸铵试剂后使用紫外可见分光光度计进行检测。 结果 磷在浓度2~15 μg/mL之间呈现良好的线性关系, r2=0.9997, 回收率为95.00%~101.20%, 相对标准偏差为2.0%。结论 该方法操作简便、准确、安全、重现性好, 能准确测定乳清蛋白营养强化粉中磷含量。

英文摘要:

      Objective To establish a method for the determination of phosphorus in whey protein fortified powder by microwave digestion spectrophotometry. Methods The whey protein nutrition fortified powder with nitric acid was added in graphite digestion apparatus for pre digestion, and 30% hydrogen peroxide was added after cooling, and then digested by microwave digestion instrument. After removing acid, the sample was transferred to a volumetric flask and the volume was fixed to the scale. After adding ammonium vanadomolybdate reagent into the diluent, the sample was detected by ultraviolet-visible spectrophotometry. Results Phosphorus showed a good linear relationship between 2–15 g/mL, r2=0.9997, and the average recovery rates were 95.00%–101.20%, with relative standard deviation 2.0%. Conclusion This method is simple, accurate, safe and reproducible, and can be used in laboratory for the determination of phosphorus content in whey protein fortified powder.