title: Determination of salivary dehydroepiandrosterone using liquid chromatography--tandem mass spectrometry combined with charged derivatization.
abstract: A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS-MS) method for the quantification of dehydroepiandrosterone (DHEA) in human saliva has been developed and validated. The saliva was deproteinized with acetonitrile, purified using a Strata-X cartridge, derivatized with the permanently charged reagent, 2-hydrazino-1-methylpyridine (HMP), and subjected to LC-MS-MS. The derivatization with HMP was very effective for increasing the detectability of DHEA in the positive-ESI-MS. Quantification was based on the selected reaction monitoring and androsterone was used as an internal standard. This method allowed the reproducible and accurate quantification of the salivary DHEA using a 200-microl sample and the limit of quantitation for DHEA was 25 pg/ml. No significant matrix effect or change in the measured value by freeze/thaw repetition was observed. The developed method was applied to clinical studies, and produced satisfactory results.
authors.affiliation: Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. higashi@p.kanazawa-u.ac.jp
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Higashi
authors.forename: Yujin
authors.initials: Y
authors.lastname: Shibayama
authors.forename: Kazutake
authors.initials: K
authors.lastname: Shimada
mesh_terms: D000328:Adult; D002853:Chromatography, Liquid / Q000379:methods*; D002940:Circadian Rhythm; D003687:Dehydroepiandrosterone / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D012015:Reference Standards; D015203:Reproducibility of Results; D012463:Saliva / Q000737:chemistry*; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003687:Dehydroepiandrosterone