Background : The reference standards of herbal medicine is used to quality control for herbal medicines. It is important that National Reference Standards maintain high stability of herbal medicines during all periods from the manufacture to the storage. In order to control quality of herbal medicines, the control reference standards (CRSs) have been produced by Ministry of Food and Drug Safety, starting from 2002. The designated CRSs are essential tests and assays to be carried out in accordance with the official compendium such as the Korean Pharmacopoeia and the Korean Herbal Pharmacopoeia.
Methods and Results : The aim of this study is to perform a stability testing for 80 national reference standards to ensure the reliability of standards. For example, there are reference standards of Sweroside, Liquiritin, Wogonin etc. First of all, We randomly select three samples of CRSs and weight them and mobile phase is made suitable for the experimental conditions. We analyzed the purity value of each CRSs in calculating absolute peak area percent, using High Performance Liquid Chromatography (HPLC) based on the method in the official compendium. And the result showed that 80 evaluted CRSs were revealed more than 95% purity value. The stability of the CRSs under storage condition (4℃) were tested annually for 3 randomly selected samples.
Conclusion : There are no significant difference among observed contents. The results of stability assessment represent suitable for quantitative analysis: less than 5% uncertainty of measurement. Even though this statistical analysis identified that stability was maintained for most of the products, some of them still need to be continuously monitored.