核磁共振法定量测定氢溴酸东莨菪碱的绝对含量

Quantitative nuclear magnetic resonance determination of the absolute content of scopolamine hydrobromide

目的:建立测定氢溴酸东莨菪碱绝对含量的核磁共振定量法(简称QNMR)。方法:采用Avance DRX 500型核磁共振谱仪,zg30脉冲序列在恒温25℃下获取1H NMR谱。以对苯二酚为内标,同时测定了氢溴酸东莨菪碱及未知杂质(乙醇)的含量。结果:分别以δ2.63及δ2.82氢溴酸东莨菪碱中的峰及对苯二酚的δ6.63的单峰作为定量峰,含量分别为91.56%与91.50%;分别以δ3.47及δ1.02乙醇中的峰及对苯二酚的δ6.63的单峰作为定量峰,含量分别为3.86%与3.80%。重复性试验的RSD为0.25%(n=5)。结论:采用核磁定量的方法,准确快捷的测定了氢溴酸东莨菪碱的绝对含量,并同时对其中的未知杂质进行了定性与定量,是对标准物质绝对含量测定的一种良好的补充方法。

Objective：To establish a quantitative nuclear magnetic Resonance method for the determination of the absolute scopolamine hydrobromide. Methods： Proton nuclear magnetic resonance spectroscopy [ 1H - NMR ] spectra were obtain in D20 with zg30 pulse sequence by using a Avance DRX 500 spectrometer at 25℃. To determine the contents of the Scopolamine Hydrobromide and the unknown impurity （ethanol） at the same time. Results：The analysis of 1H - NMR spectrum of Scopolamine Hydrobromide mixed with p - dihydroxybenzene as internal standard in D20 revealed that the integration of signals at 8 2.63 ppm and 8 2. 82 ppm of the Scopolamine Hydrobromide and δ6.63 ppm of p - dihydroxybenzene could used for quantitation respectively and the results of the contents of Scopolamine Hydrobromide were 91.56% and 91.50%. It also revealed that the integration of signals at 8 3.47 ppm and 8 1.02 ppm of the ethanol that consist in the Scopolamine Hydrobromide and 8 6.63 ppm of p - dihydroxy- benzene could used for quantitation, respectively and the results of the contents of ethanol were 3.86% and 3.80%. The precision RSD was 0. 25% （n = 5）. Conclusion： QNMR can be used for the quantitative determination the absolute content of scopolamine hydrobromide rapidly, and it also can be determine the unknown impurity of the Scopolamine Hydrobromide qualitatively and quantitatively. It is a good supplementary method for determination the absolute content of the reference standard.