化学分析法精确测定羟基磷灰石中的Ca和P含量

Precise Measurement of Ca and P Content in Hydroxyapatite by Chemical Analysis

分别采用改进的EDTA络合滴定法和高锰酸钾氧化返滴法精确测定了羟基磷灰石(HA)等物质中的钙含量,通过对比实验、精密度实验和加标回收实验对基准碳酸钙、分析纯磷酸三钙、分析纯磷酸氢钙及合成的羟基磷灰石中的钙含量进行了测定,对结果的标准偏差、相对标准偏差及回收率做了比较分析和讨论。结果表明,两种方法测定结果相当吻合,改进的EDTA法比高锰酸钾法更快速、简便,能够满足钙磷酸盐中钙含量的准确测定。钙含量测定的最大标准偏差和相对标准偏差分别为0.057和0.15%。同时,采用磷钼酸喹啉容量法测定了样品中的磷含量。

The contents of Ca and P in hydroxyapatite were precisely measured using the improved EDTA complex titration and potassium permanganate oxidimetry respectively. Through comparative test, precision test and recovery fraction test, the contents of Ca and P in standard CaCO3, Ca3 （ PO4 ） 2, CaHPO4·2H2O and Ca10 （PO4）5 （OH）2 were determined and calculated. The standard deviation, relative standard deviation and recovery rate resulted from the both method were discussed and analysised. It is shown that the results obtained from the two analytical method are quite agreeable to each other, but the improved EDTA method is more simple and fast and can be applied to decide the Ca content accurately. The biggest standard deviation and relative standard deviation for Ca content test are 0.057and 0.15 %, respectively. The P contents were also determined by phosphomolybdate-quinoline precipitate method.