title: Determination of ambroxol in human plasma using LC-MS/MS.
abstract: A sensitive and selective liquid chromatographic method coupled with tandem mass spectrometry (LC-MS/MS) was developed for the quantification of ambroxol in human plasma. Domperidone was used as internal standard, with plasma samples extracted using diethyl ether under basic condition. A centrifuged upper layer was then evaporated and reconstituted with 200 microl methanol. The reconstituted samples were injected into a C(18) XTerra MS column (2.1 x 30 mm) with 3.5 microm particle size. The analytical column lasted for at least 600 injections. The mobile phase was composed of 20 mM ammonium acetate in 90% acetonitrile (pH 8.8), with flow rate at 250 microl/min. The mass spectrometer was operated in positive ion mode using turbo electrospray ionization. Nitrogen was used as the nebulizer, curtain, collision, and auxiliary gases. Using MS/MS with multiple reaction monitoring (MRM) mode, ambroxol was detected without severe interferences from plasma matrix. Ambroxol produced a protonated precursor ion ([M+H](+)) at m/z 379 and a corresponding product ion at m/z 264. And internal standard (domperidone) produced a protonated precursor ion ([M+H](+)) at m/z 426 and a corresponding product ion at m/z 174. Detection of ambroxol in human plasma was accurate and precise, with quantification limit at 0.2 ng/ml. This method has been successfully applied to a study of ambroxol in human specimens.
authors.affiliation: Department of Pharmacokinetics, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14 Dongbinggo-dong, Yongsan-gu, Seoul 140-809, South Korea. novakims@yahoo.com
authors.forename: Hohyun
authors.initials: H
authors.lastname: Kim
authors.forename: Jeong-Yeon
authors.initials: JY
authors.lastname: Yoo
authors.forename: Sang Beom
authors.initials: SB
authors.lastname: Han
authors.forename: Hee Joo
authors.initials: HJ
authors.lastname: Lee
authors.forename: Kyung Ryul
authors.initials: KR
authors.lastname: Lee
mesh_terms: D000328:Adult; D000551:Ambroxol / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods
chemical_list: D000551:Ambroxol