title: Pipette tip solid-phase extraction and high-performance liquid chromatography for the determination of flavonoids from Epimedii herba in rat serum and application of the technique to pharmacokinetic studies.
abstract: Epimedii herba is a traditional Chinese medicine for the treatment of osteoporosis. Epimedin A, B and C and icariin are the primary effective ingredients of this medicine. In this study, a simple and low-cost method based on pipette tip solid-phase extraction, high-performance liquid chromatography separation, and diode array detection has been developed for the simultaneous analysis of four flavonoids (epimedin A, B and C and icariin) from Epimedii herba in rat serum samples. In this novel extraction configuration, the sorbents were placed between a filter (hollow fiber) and the pipette tip. Pipette tip solid-phase extraction has several advantages compared to conventional extraction methods: faster extraction time (6.0min); lower sample volume (100μL); lower solvent volume (100μL); and less solvent waste. Under the optimum extraction conditions, the method showed good linearity (0.05-10.0μgmL(-1)), acceptable intra- and inter precision (RSD<6%), low limits of quantification (0.027-0.045μgmL(-1)) and satisfactory relative recoveries (98.63-103.18%). This method was successfully applied to investigate the pharmacokinetics of the major flavonoids in Epimedii herba extract after oral administration to rats (10gkg(-1) body weight). The primary pharmacokinetic parameters for rats were determined as follows: Cmax, 0.45-4.11μgmL(-1); Tmax, 0.21-0.26h; t1/2α, 0.06-0.12h; t1/2β, 2.02-3.48h; AUC0-∞: 0.50-2.58μghmL(-1); CL, 19.53-44.72Lkg(-1)h(-1); and MRT0-∞, 2.25-3.77h. The developed method has the potential to promulgate the pharmacokinetics and provide more information for clinical applications.
authors: Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
authors: Nani
authors: N
authors: Wang
authors: Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
authors: Xiaowen
authors: X
authors: Huang
authors: Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
authors: Xuping
authors: X
authors: Wang
authors: Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
authors: Yang
authors: Y
authors: Zhang
authors: Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
authors: Renjie
authors: R
authors: Wu
authors: Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, China. Electronic address: shoudanok@163.com.
authors: Dan
authors: D
authors: Shou
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D034181:Epimedium; D005260:Female; D005419:Flavonoids / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics*; D016014:Linear Models; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D004365:Drugs, Chinese Herbal; D005419:Flavonoids
keywords: Epimedii herba; Flavonoids; Pharmacokinetics; Pipette tip extraction; Serum