title: Lithium adduct as precursor ion for sensitive and rapid quantification of 20 (S)-protopanaxadiol in rat plasma by liquid chromatography/quadrupole linear ion trap mass spectrometry and application to rat pharmacokinetic study.
abstract: A novel, rapid and sensitive liquid chromatography/quadrupole linear ion trap mass spectrometry [LC-ESI-(QqLIT)MS/MS] method was developed and validated for the quantification of protopanaxadiol (PPD) in rat plasma. Oleanolic acid (OA) was used as internal standard (IS). A simple protein precipitation based on acetonitrile (ACN) was employed. Chromatographic separation was performed on a Sepax GP-C18 column (50 × 2.1 mm, 5 μM) with a mobile phase consisting of ACN-water and 1.5 μM formic acid and 25 mM lithium acetate (90 : 10, v/v) at a flow rate of 0.4 ml/min for 3.0 min. Multiple-reaction-monitoring mode was performed using lithium adduct ion as precursor ion of m/z 467.5/449.4 and 455.6/407.4 for the drug and IS, respectively. Calibration curve was recovered over a concentration range of 0.5-100 ng/ml with a correlation coefficient >0.99. The limit of detection was 0.2 ng/ml in rat plasma for PPD. The results of the intraday and interday precision and accuracy studies were well within the acceptable limits. The validated method was successfully applied to investigate the pharmacokinetic study of PPD after intravenous and gavage administration to rat.
authors.affiliation: Sundia MediTech Company Ltd., 388 Jialilue Road Building 9, Zhangjiang High-Tech Park, Shanghai 201203, China.
authors.forename: Yuanwu
authors.initials: Y
authors.lastname: Bao
authors.forename: Quanying
authors.initials: Q
authors.lastname: Wang
authors.forename: Pingming
authors.initials: P
authors.lastname: Tang
mesh_terms: D000818:Animals; D000928:Antidepressive Agents / Q000097:blood* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000191:economics / Q000379:methods; D057230:Limit of Detection; D008094:Lithium / Q000737:chemistry; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012502:Sapogenins / Q000097:blood* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000191:economics / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000191:economics / Q000379:methods*; D013997:Time Factors
chemical_list: D000928:Antidepressive Agents; D012502:Sapogenins; D008094:Lithium; C062916:protopanaxadiol