title: Determination of huperzine A in human plasma by liquid chromatography-electrospray tandem mass spectrometry: application to a bioequivalence study on Chinese volunteers.
abstract: A simple, sensitive and selective LC-MS-MS method has been developed for the quantification of huperzine A in human plasma. Huperzine A and pseudoephedrine hydrochloride (internal standard) were isolated from human plasma by extraction with ethyl acetate, chromatographed on a C(18) column with a mobile phase consisting of 0.2% formic acid-methanol (15:85, v/v) and detected using a tandem mass spectrometer with an electrospray ionization interface. The lower limit of quantification was 0.0508 ng/mL, and the assay exhibited a linear range of 0.0508-5.08 ng/mL (r = 0.9998). The method was successfully applied to investigate the bioequivalence between two kinds of tablets (test vs reference product) in 18 healthy male Chinese volunteers. After a single 0.2 mg dose for the test and reference product, the resulting means of major pharmacokinetic parameters such as AUC(0-24), AUC(0-infinity), C(max), T(max) and t(1/2) of huperzine A were 16.35 +/- 3.42 vs 16.38 +/- 3.61 ng h/mL, 17.53 +/- 3.80 vs 17.70 +/- 3.97 ng h/mL, 2.47 +/- 0.49 vs 2.51 +/- 0.51 ng/mL, 1.3 +/- 0.4 vs 1.2 +/- 0.3 h and 5.92 +/- 0.75 vs 6.18 +/- 0.66 h, respectively, indicating that these two kinds of tablets were bioequivalent.
authors.affiliation: School of Pharmaceutical Science, Nanjing Medical University, Nanjing 210029, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Jianhua
authors.initials: J
authors.lastname: Li
authors.forename: Qin
authors.initials: Q
authors.lastname: Hu
mesh_terms: D000470:Alkaloids; D044466:Asian People; D002681:China; D006801:Humans; D015394:Molecular Structure; D015203:Reproducibility of Results; D012717:Sesquiterpenes / Q000097:blood* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000470:Alkaloids; D012717:Sesquiterpenes; C050426:huperzine A