OBJECTIVE: To determine the content（ indigo and indirubin） in indigo naturalis

indigo naturalis decoction and indigo naturalis formula granules from different manufacturers

and to analyze the content difference

so as to explore the rational clinical administration of indigo naturalis. METHODS: The separation was performed on the Waters XBridge C

18

column（ 4. 6 mm × 250 mm

5 μm） by using liquid phase detection

with sample size of 10 μl.The mobile phase was methanol-water（ V∶ V = 70 ∶ 30）

and the flow rate was 1. 0 ml/min. The column temperature was 35 ℃ ． The detection wavelength of PDA detector was 606 nm（ indigo） and 292 nm（ indirubin）

the contents of indigo and indirubin in indigo naturalis decoction pieces

decoction and granules were determined. RESULTS: The contents of indigo and indirubin in indigo naturalis decoction pieces were 15. 5% and 0. 18%

the contents of indigo and indirubin in indigo naturalis granules 1 were 4. 9% and 0. 14%

and the contents of indigo and indirubin in indigo naturalis granules 2 were 8. 8% and 0. 13%

all of which met the requirements of the Pharmacopoeia of the People’s Republic of China（ Part Ⅰ

2020 edition）（ the range of indigo was no less than 2%

the range of indirubin was no less than 0. 13%）. Among the indigo naturalis decoction pieces

decoction and granules

the content of indigo and indirubin was the highest in indigo naturalis decoction pieces. CONCLUSIONS: According to the experimental results

it is clinically recommended to use indigo naturalis decoction pieces for direct brewing or into pills and dispersal

which is more effective

rather than indigo naturalis packet decoction.