Determination of Total Anthraauinones Content in Rubia cordifolia

Total anthraauinones content in Rubia cordifolia was determined by differential ultraviolet spectrophotometry to explore its measuring method.The results showed that the absorption value(△A) and the concentration(C) had good linear relationship(ΔA= 39.87C-0.0042,r= 0.9996,n=6) with the average recovery of 99.97%(RSD=0.62%),All above indicate that this method is accurate,credible,stable with high sensitivity.