RESUMEN
In this paper, we aim to control and evaluate the quality of Liuwei Dihuang Concentrated Pill by using the model of fingerprint technique and "component structure" theory. Agilent 5 TC-C_(18) column(4.6 mm×250 mm,5 μm) was used, with 0.1% formic acid solution-acetonitrile as mobile phase at a flow rate of 1.0 mL·min~(-1). The column temperature was 30 ℃, with detection wavelength of 242 nm and the sample volume of 10 μL. The characteristic fingerprint of Liuwei Dihuang Concentrated Pill was established by high performance liquid chromatography(HPLC) for its quality control. Seventeen common peaks were identified, and the similarity was 0.550-0.997 in 29 batches of samples, indicating that the quality difference among batches of Liuwei Dihuang Concentrated Pills was significant. The structural characteristics of the Moutan Cortex components in Liuwei Dihuang Concentrated Pills were characterized. On this basis, combined with the structural characteristics of genuine components of Moutan Cortex, the structural characteristics of components in Liuwei Dihuang Concentrated Pills were further analyzed. The results showed that there were significant differences in the contents and quantity ratios of 9 representative components(components) of Moutan Cortex in Liuwei Dihuang Concentrated Pills from different manufacturers, indicating internal quality differences among different batches of products. The fingerprint technique and the "component structure" theory established by the above research provide an analytical method and a research foundation for the quality evaluation of Liuwei Dihuang Concentrated Pills.