QZWTT was provided by Liaoning Huarun Benxi Sanyao Co. Ltd(Benxi, China, lot no. 20200101). We used 26 chemical referencestandards in this study (Chengdu Pufeide BioTechnology Co. Ltd,Cheng du, China or Weikeqi Biological Technology Co. Ltd, Chengdu,China; Table S1). The acetonitrile, methanol (Merck, Germany) andformic acid (Fisher, USA) were of LC–MS grade, whereas the remain-ing chemicals were of analytically grade.

Protopine, coptisine, allocryptopine, tetrahydropalmatine,tetrahydrocoptisine, tetrahydroberberine, corynoline, coryda-line, and dehydrocorydaline were procured from SichuanWeikeqi Bio-technological. The purities of the nine alkaloidsare>98.5%. Nitidine chloride (purity>98.5%, internal stan-dard, IS) was supplied by Shanghai Yuanye Biological Tech-nology.

Nine alkaloids standards with their purity >98.5% were purchased from Sichuan Weikeqi Bio-technological Co., including corydaline, dehydrocorydaline, corynoline, tetrahydroberberine, tetrahydrocoptisine, tetrahydropalmatine, allocryptopine, coptisine and protopine. Nitidine chloride (purity>98.5%, internal standard, IS) was obtained from Shanghai Yuanye Biological Technology Co. The root of Corydalis turtschaninovii was collected in Hebei Province (lot: 150715). Methanol and acetonitrile of HPLC-MS grade were provided by Merck Co. Distilled water was obtained from a Milli-Q water purification system.