ABSTRACT
OBJECTIVE To establish a method for simultaneous determi nation of six components in Melastoma dodecandrum and investigate its correlation with antioxidant activity. METHODS Ultra high-performance liquid chromatography （UPLC）method was adopted. The contents of gallic acid ，protocatechuic acid ，isovitexin，rutin and ellagic acid in 23 batches of M. dodecandrum were determined by quantitative analysis of multi-components by single-marker （QAMS）method，using vitexin as the internal reference. Then 1，1-diphenyl-2-picrylhydrazyl（DPPH）free radical method ，2，2′-azino-bis（3-ethylbenzothiazoline-6-sulfonic acid ） diammonium salt （ABTS）method and ferric ion reduction/antioxidant power （FRAP）method were applied to determine the antioxidant activity of 23 batches of M. dodecandrum . Grey correlation analysis and bivariate correlation analysis were used to evaluate the correlation between six components and antioxidant activity. RESULTS The content of vitexin were 0.021％-0.182％. The contents of gallic acid ，protocatechuic acid ，isovitexin，rutin and ellagic acid by QAMS method were 0.008％-0.042％， 0.003％-0.023％，0.071％-0.283％，0.013％-0.140％ and 0.006％-0.021％，respectively. Compared with the results of external standard method ，P was greater than 0.05. Grey correlation analysis showed that the grey correlation coefficients between the contents of six components an d antioxidant activity was 0.727 6- 0.866 9. Bivariate correlation analysis showed that the contents of vitexin ，isovitexin and rutin were positively correlated with antioxidant activity （P＜0.05 or P＜0.01），the content of gallic acid and protocatechuic acid were negatively correlated with antioxidant activity （P＜0.05）. There was no significant correlation between ellagic acid and antioxidant activity.CONCLUSIONS QAMS method is successfully established for the simultaneous determination of six components in M. dodecandrum. The six components in M. dodecandrum are highly correlated with antioxidant activity.
ABSTRACT
OBJECTIVE: To determine the content of tobramycin in Tobramycin Dexamethasone Eye Drops by HPLC-ELSD.METHODS: The sample was separated on VP-ODS C18 column.The mobile phase was 1.0% trifluoroacetic acid-methanol(95∶5) at a flow rate of 1.0 mL?min-1.The drift tube temprature was 45 ℃;the pressure of nebulizing gas was 3.5 bar,and the detection wavelength was set at 254 nm.RESULTS: The liner range of tobramycin was 156.0～436.0 ?g?mL-1(r=0.999 7).The limit of detection was 0.523 ?g and the limit of quantification was 1.744 ?g.The average recovery was 99.57%(RSD=0.92%).CONCLUSION: The method is accurate,reliable,specific,and suitable for the quality control of Tobramycin Dexamethasone Eye Drops.
ABSTRACT
This paper reported TLC identification of various Chinese medicines in Renshensinitang Oral Liq- uid,limit dose detection and content determination of aconitine.These methods could be available for internal quality control of Renshensinitang Oral Liquid.