离子色谱法测定食品添加剂磷酸二氢钙中的阴离子

Determination of anion in the calcium phosphate of food additives by ion chromatography

目的建立一种同时测定磷酸二氢钙中的F-、Cl-、SO42-、NO3-4种阴离子的分析方法。方法以碳酸钠和氢氧化钠溶液为淋洗液,通过对淋洗液等色谱分析条件的优化,选择离子色谱法测定食品添加剂CaH2PO4中的阴离子,以标准物质保留时间定性,以外标法定量。结果在优化的色谱条件下,4种离子的分离度好,检测灵敏度高;被测离子的浓度在一定范围内与色谱峰面积呈良好的线性关系,相关系数r>0.999。4种离子测定结果相对标准偏差均<3%(n=9),平均加标回收率为80%～105%。结论离子色谱法简便、灵敏、快速,能够满足同时测定CaH2PO4中4种阴离子含量的要求。

Objective A new analytical method was developed to simultaneously determine fluoride ion, chloride ion, sulfate and nitrate in calcium phosphate. Method The chromatography conditions were optimized, and the anions of calcium phosphate were determined by ion chromatography with elution of sodium carbonate and sodium hydroxide. The pesticides were identified by retention time and quantified by external standards. Results The results showed that the four ions were separated with high sensitivity in the optimized experiment conditions. Concentration of each ion was linear with its peak area, and the correlation coefficient was above 0. 999. The RSD of the detection results was less than 3% （ n = 9 ） , and the recoveries were 80% - 105%. Conclusion This method is simple, sensitive and rapid for the simultaneous determination of four kinds of anions content in calcium phosphate.