All the medicinal materials were tested, and their quality met the relevant standards of the 2020 edition of the Chinese Pharmacopoeia. Standard reference compounds, including epiberberine (wkq20031807), coptisine (wkq20021306), palmatine (wkq20051201), berberine (wkq20032408), baicalin (wkq20010908), wogonoside (wkq20040108), baicalein (wkq20022608), wogonin (20030204), rhein (wkq20052209), aloe-emodin (wkq20032708), emodin (wkq20041308), chrysophanol (wkq20081705), and physcion (wkq20040101) were purchased from Weikeqi Biotechnology Co., Ltd (Chengdu, China). The purity of all standard products was higher than 98%. Chromatographic grade acetonitrile and formic acid were purchased from Thermo-Fisher (US).

The TWMM was provided by Beijing HanDian Pharmaceutical Co., Ltd. (Beijing, China). Chlorogenic acid, linarin, luteolin, jaspolyside, tolbutamide, stachydrine, magnoflorine, calycosin-7-O-β-d-glucoside, stepharanine, jatrorrhizine, epiberberine, columbamine, ononin, berberine, palmatine, berberrubine, calycosin, formononetin, 2α-hydroxyoleanic acid, hydroxytyrosol, salidroside, luteolin-7-O-glucoside, verbascoside, specnuezhenide, oleuropein, physcion, oleonuezhenide, astragaloside IV, astragaloside II, isoastragaloside II, astragaloside I, luteolin, formononetin, and tolbutamide (purity ≥ 98%) were purchased from Shanghai Yuanye Pharmaceutical Technology Co., Ltd and Sichuan Weikeqi Pharmaceutical Technology Co., Ltd. Acetonitrile and formic acid both in HPLC grade were obtained from Fisher Scientific (Fair Lawn, NJ, USA). Ultrapure water was prepared using a Milli-Q water purification system (Millipore, Bredford, MA, USA). Other reagents were all analytical grade.

Reference standards of (1) loganic acid (Lot no. 131220); (5) scutellarin (130306); (8) apigetrin (130315); (11) baicalin (121128); (12) eriodictyol (130606); (13) quercetin (131120); (14) scutellarein (131219); (15) oroxyloside (121122); (17) wogonoside (131214); (18) baicalein (130119); (19) aloe-emodin (130425); (21) wogonin (140521) and (23) oroxylin A (130323) were provided by Chengdu Preferred Biotechnology Co. Ltd. (Chengdu, China). Reference compounds of (3) daidzin (131214); (4) sennoside B (130409); (6) luteoloside (130418); (7) sennoside A (130306); (9) rhaponticin (140604); (10) daidzein (130715); (16) physcion (140211); (20) rhein (131024); (22) chrysophanol (140219); (24) emodin (140422); (25) coptisine (130628); (26) epiberberine (130621); (27) jatrorrhizine hydrochloride (130318); (28) palmatine hydrochloride (130702) and (29) berberine hydrochloride (140314) were provided by Sichuan Weikeqi Biological Technology Co., Ltd. (Chengdu, China). Reference marker of (2) caffeic acid (130428) was provided by Chengdu Herbpurify Co., Ltd. (Chengdu, China).

SK injection samples were manufactured by Xi'an Shi Ji Sheng Kang Pharmaceutical industry (Xi'an, China). The samples were diluted by four times to inject. The reference standards aloe-emodin, rhein, emodin, chrysophanol, physcion and astragaloside IV were purchased from Chengdu Weikeqi Bio-technology (Sichuan, China). Gallic acid, chlorogenic acid, caffeic acid, ferulic acid, rosmarinic acid, ethyl ferulate, protocatechuic acid, protocatechu aldehyde, catechin, hydroxysafflor yellow A

PMR was purchased from Tong Ren Tang Technologies Co. Ltd. THSG (batch number: 140317), emodin (batch number: 140422), EG (batch number: 140822), and physcion (batch number: 140211) were purchased from Sichuan Weikeqi Biological Technology Co., Ltd. Cimetidine for injection (Jiangsu Shenlong Pharmaceutical Co., Ltd.; standard: 2?mL, 200?mg per ampoule, batch number: 070314) and trans-1,2-dichloroethylene were purchased from Sigma Company (product number: C62209-5G).