摘要
The research on the application of X-ray diffraction in the quantitative analysis of Chinese medicines is rare. The main reason is that the technical problems related to the internal standard and the selection of quantitative peaks are not well solved, and the accuracy and precision of the results are not satisfactory. This study employed the concept of mass absorption coefficient based on the internal standard method, and the full spectrum fitting and quantitative methods were used to solve the above technical problems. The sample was blended. the internal standard substance of zinc oxide was fully ground, and tablets were prepared by positive pressure method. Under certain instrumental conditions, the PXRD pattern was obtained by scanning. The percentage of gypsum fibrosum in Xiaokening tablet was obtained by quantitative analysis of full spectrum fitting internal standard by TOPAS software. The method was investigated by methodology. At the same time, the method was compared by ion chromatography, and SPSS software was used to make a significant t test on the results of the two methods. After the investigation, the average standard recovery rate of CaSO4-2H2O was 99.06%(RSD = 3.02%);and the recovery rate for simulated samples was 96.7%. The method had good specificity. After statistical analysis, there was no significant difference between the new PXRD method and the traditional method of ion chromatography.
粉末X射线衍射法用于中药定量的研究很少见,主要原因是未能很好解决内标物和定量峰选择等相关的技术问题,结果的准确度和精密度不尽人意。本研究引入质量吸收系数这一概念,基于内标法采用全谱拟合定量,解决了上述技术问题。将样品与内标物质氧化锌充分研磨混匀,采用正压法进行压片,在一定仪器条件下,扫描获得PXRD图谱,通过TOPAS软件进行内标定量分析,得到石膏的百分含量。对该方法进行方法学考察同时采用离子色谱法。经考察,方法的平均加标回收率为99.06%(RSD=3.02%),模拟样回收率平均值为96.7%,表明该方法的准确度良好。经统计分析,新建的PXRD方法与传统的离子色谱方法无显著性差异。
