定量核磁共振氢谱法测定那屈肝素钙中钙离子的含量

Determination of calcium ion content in nadroparin calcium by quantitative proton nuclear magnetic resonance spectroscopy

目的:建立采用定量核磁共振氢谱法(qHNMR法)测定那屈肝素钙中钙离子含量。方法:采集核磁共振氢谱(1H NMR),zg 30脉冲,弛豫延迟时间为15 s,选择乙二胺四乙酸(EDTA)与钙离子络合物Ca-EDTA的信号峰作为钙离子的定量峰,以马来酸为内标物,对那屈肝素钙中钙离子进行定量分析。结果:Ca-EDTA和马来酸定量峰信号在1H NMR谱上分离度良好,样品与内标物的质量比在0.546~12.238,与其定量峰面积比呈线性关系(r=0.999 9),精密度RSD为0.65%,重复性RSD为0.77%,平均加样回收率为99.7%(RSD为1.3%),采用qHNMR测定9批那屈肝素钙样品中钙离子含量为9.54%~9.99%,测定结果与电感耦合等离子体发射光谱法(ICP-AES)测定结果基本一致。结论:建立的qHNMR法操作简便、快速、准确,可用于那屈肝素钙中钙离子含量的测定。

Objective:To establish a quantitative proton nuclear magnetic resonance(qHNMR)spectroscopy method for the determination of calcium ion content in nadroparin calcium.Methods:Proton nuclear magnetic resonance(1'H NMR)spectra,zg 30 pulses were collected,the relaxation delay time was 15 s,the signal peak of ethylenediaminetetraacetic acid(EDTA)and calcium ion complex Ca-EDTA was selected as the quantitative peak of calcium ion,maleic acid was used as the internal standard,the quantitative analysis of calcium ions in nadroparin calcium was carried out.Results:The quantitative peak signals of Ca-EDTA and maleic acid were well resolved in 1H NMR spectrum,andthe mass ratio of sample to internal standard was in the range of 0.546-12.238,the quantitative peak area ratio showed a good linear relationship(r=0.9999),the precision RSD was 0.65%,repeatability RSD was 0.77%,the average recovery was 99.7%(RSD was 1.3%).The test results of calcium ion content in nadroparin calcium fromnine batches determined by qHNMR were 9.54%-9.99%,and the results were basically consistent with those determined by ICP-AES.Conclusion:The established qHNMR method is simple,rapid,and accurate.It can be used for the determination of calcium ion content in nadroparin calcium.