不同龄养殖珍珠粉中钙的分析与测定

Study on the Variation of Calcium Content of Different Growing-period Pearl Powder

目的建立珍珠粉钙的测定方法,研究不同龄珍珠粉中钙的变化规律或含量动态范围。方法以EDTA-2Na为络合剂、抗坏血酸为抗氧剂、乙二胺四乙酸络合硫酸镁试液为滴定终点判断增敏剂、铬黑T为滴定终点指示剂进行直接滴定。结果方法有良好的重复性(RSD%=0.02%),回收率为99.89%(RSD=0.14%)符合定量要求。同时测定了1～5年龄的珠珍粉的碳酸钙含量。结论所建立的方法简便快捷,结果准确,可作为珍珠粉钙的测定方法;并提示,不同龄养殖珍珠粉中碳酸钙的含量无递变性规律,其含量动态范围为94.1%～94.8%。

Objective To establish the determination method of calcium in pearl powder and study on the variation of calcium content of different growing-period pearl powder.Methods Taking EDTA-2Na as complexing agent, Vitamine C as antioxidant agent, Magnesium Sulfate as sensitizing agent of titration end point, and chrome black T as the indicator of titration, the calcium content was determined by direct complexometric titration.Results The method has good precision(RSD%=0.02%), and recovery of 99.89%(RSD=0.14%).Conc...