To improve and perfect the quality standards and propose recommendations for the revision of quality standards for Andrographis Herba and its processed slices in Chinese Pharmacopoeia(ChP)(2020 edition) based on the problems and limitations in ChP(2015 edition). TLC identification method with andrographolide and control herbs as references was established using silica gel G thin layer plate, with chloroform-methylbenzene-methanol(8∶1∶1) as developing solvent, and 10% sulfuric acid ethanol solution as colour-developing agent. This method has good reproducibility, strong specificity and high sensitivity. As compared with the original method in ChP 2015, this method has better development effect and clearer spots. Based on the previous research, a quantitative analysis of multi-components by single-marker(QAMS) method with andrographolide as the internal reference substance was developed to simultaneously determine the contents of 4 diterpene lactones: andrographolide(S), neoandrographolide(A), 14-deoxyandrographolide(B), and dehydroandrographolide(C). The relative correction factors of f_(A/S), f_(B/S), and f_(C/S) were determined as 1.12, 0.79, and 0.63, respectively. The relative retention time of t_(A/S), t_(B/S), and t_(C/S) was 1.95, 2.18, and 2.25, respectively. According to the content determination results in 46 batches of crude drugs and 38 batches of processed slices, it was stipulated that the total contents of 4 diterpene lactones should not be less than 1.5% and 1.2% in crude drugs and processed slices, respectively. As compared with the original method in ChP 2015, the present QAMS method could not only reduce the detection cost and improve the efficiency, but also can be used to evaluate the quality of Andrographis Herba and its processed slices more comprehensively and objectively. Diterpene lactones are generally recognized as the effective components in Andrographis Herba, and their contents in leaves were much higher than those in stems. However, almost all of the current commercial processed slices are processed from stems, so their quality is gene-rally poor and the efficacy is hard to be guaranteed. Therefore, the weight percentage of leaves should be added into the inspection items of the processed slices and it should not be less than 25%.
Keywords: Andrographis Herba; QAMS(quantitative analysis of multi-components by single-marker); TLC identification; content determination; quality standard.