OBJECTIVE

2

To establish the detection method for the adulteration of

Bupleurum marginatum

in Ganmao qingre granules， and to determine the adulteration limit.

METHODS

2

HPLC-MS/MS method was used to detect the content of nepasaikosaponin K in commercial and self-made samples of Ganmao qingre granules，using electrospray ionization， and the analysis was carried out under multiple reaction monitoring model in negative mode with

m

/

z

943.6→635.5　as the quantitative ion pair. The calculation method was established for the adulteration proportion of

B. marginatum

in Ganmao qingre granules. Taking nepasaikosaponin K as the

index， the adulteration limit was determined.

RESULTS

2

The linear range of nepasaikosaponin K were 0.051-20.200 μg/mL （

r

＝0.999 1）. RSDs of precision， repeatability and stability （24 h） tests were all lower than 2.50%.　The average recoveries were 97.58% （RSD＝2.09%，

n

＝9）. The limit of detection was 0.60 μg/g， the limit of quantitation was 1.80 μg/g. The adulteration ratio of

B. marginatum

in Ganmao qingre granules had a good linear relationship to the peak area of nepasaikosaponin K in the range of 5%-100% （

r

＝0.990 9）. The contents of nepasaikosaponin K in 15 batches of Ganmao qingre granules were 2.584-56.661 μg/g. One batch of samples exceeded the proposed adulteration limit（10%）， and the unqualified rate was 6.67%.

CONCLUSIONS

2

The established analytical method can be used to detect the adulteration of

B. marginatum

in Ganmao qinggre granules， the proposed adulteration limit is 10%.