title: Microsomal metabolism of calycosin, formononetin and drug-drug interactions by dynamic microdialysis sampling and HPLC-DAD-MS analysis.
abstract: A dynamic microdialysis sampling method with liquid chromatography-diode array detection and time-of-flight mass spectrometry (LC-DAD-TOF/MS) analysis was developed to investigate rat microsomal metabolisms of calycosin and formononetin, and their drug-drug interactions. Two hydroxylated metabolites from calycosin, and three hydroxylated or 4'-O-demethylated derivatives from formononetin were detected and identified after co-incubation with microsomes. Calibration curves offered linear ranges of two orders of magnitude with r(2)>0.999 for calycosin, formononetin and daidzein. The quantitative LC method provides a range of 0.028-0.034microg/mL for limits of detection, overall precision less than 5% and accuracy less than 3% by RSD. Besides, calycosin and formononetin were found to produce the depressive effect on the CYP450 enzyme reaction, and inhibit phase I enzyme reaction of each other when they are concurrent. Dynamic microdialysis sampling with LC-DAD-TOF/MS analysis developed in this work is a powerful tool for in vitro metabolism studies of drugs and metabolic interactions.
authors.affiliation: China Pharmaceutical University, Ministry of Education, Nanjing, China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Wen
authors.forename: Lian-Wen
authors.initials: LW
authors.lastname: Qi
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Ling
authors.initials: L
authors.lastname: Yi
authors.forename: Ya-Qiong
authors.initials: YQ
authors.lastname: Wang
authors.forename: E-Hu
authors.initials: EH
authors.lastname: Liu
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Yang
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004347:Drug Interactions; D007529:Isoflavones / Q000378:metabolism*; D013058:Mass Spectrometry / Q000379:methods*; D017551:Microdialysis; D008861:Microsomes / Q000378:metabolism*; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D007529:Isoflavones; C121707:7,3'-dihydroxy-4'-methoxyisoflavone; C007768:formononetin