Quantitative determination of Astragaloside IV, a natural product with cardioprotective activity, in plasma, urine and other biological samples by HPLC coupled with tandem mass spectrometry.
Astragaloside IV is a novel cardioprotective agent extracted from the Chinese medical herb Astragalus membranaceus (Fisch) Bge. This agent is being developed for treatment for cardiovascular disease. Further development of Astragaloside IV will require detailed pharmacokinetic studies in preclinical animal models. Therefore, we established a sensitive and accurate high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (LC/MS/MS) quantitative detection method for measurement of Astragaloside IV levels in plasma, urine as well as other biological samples including bile fluid, feces and various tissues. Extraction of Astragaloside IV from plasma and other biological samples was performed by Waters OASIS(trade mark) solid phase extraction column by washing with water and eluting with methanol, respectively. An aliquot of extracted residues was injected into LC/MS/MS system with separation by a Cosmosil C18 5 microm, 150 mm x 2.0 mm) column. Acetonitrile:water containing 5 microM NaAc (40:60, v/v) was used as a mobile phase. The eluted compounds were detected by tandem mass spectrometry. The average extraction recoveries were greater than 89% for Astragaloside IV and digoxin from plasma, while extraction recovery of Astragaloside IV and digoxin from tissues, bile fluid, urine and fece ranged from 61 to 85%, respectively. Good linearity (R2>0.9999) was observed throughout the range of 10-5000 ng/ml in 0.5 ml rat plasma and 5-5000 ng/ml in 0.5 ml dog plasma. In addition, good linearity (R2>0.9999) was also observed in urine, bile fluid, feces samples and various tissue samples. The overall accuracy of this method was 93-110% for both rat plasma and dog plasma. Intra-assay and inter-assay variabilities were less than 15.03% in plasma. The lowest quantitation limit of Astragaloside IV was 10 ng/ml in 0.5 ml rat plasma and 5 ng/ml in 0.5 ml dog plasma, respectively. Practical utility of this new LC/MS/MS method was confirmed in pilot pharmacokinetic studies in both rats and dogs following intravenous administration.
Zhang
Weidong
W
Department of Natural Medicinal Chemistry, Second Military Medical University, 325 Guohe Rd., Shanghai 200433, PR China. wdzhangy@hotmail.com
Zhang
Chuan
C
Liu
Runhui
R
Li
Huiliang
H
Zhang
Jintao
J
Mao
Chen
C
Chen
Chunlin
C
D000818:Animals; D002316:Cardiotonic Agents / Q000032:analysis* / Q000097:blood / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004285:Dogs; D004355:Drug Stability; D004365:Drugs, Chinese Herbal / Q000032:analysis*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012503:Saponins / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics / Q000652:urine; D012680:Sensitivity and Specificity; D014315:Triterpenes / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics / Q000652:urine
D002316:Cardiotonic Agents; D004365:Drugs, Chinese Herbal; D012503:Saponins; D014315:Triterpenes; C052064:astragaloside A