title: Determination of prostatic androgens in 10 mg of tissue using liquid chromatography-tandem mass spectrometry with charged derivatization.
abstract: A practical liquid chromatography-tandem mass spectrometric (LC-MS-MS) method for the determination of prostatic 5alpha-dihydrotestosterone (DHT) and testosterone (T) has been developed. The prostatic androgens were extracted with MeOH-H2O (3:7, v/v), purified with an Oasis HLB cartridge, derivatized with the permanently charged reagent 2-hydrazino-1-methylpyridine (HMP), and subjected to LC-MS-MS analysis using electrospray ionization (ESI) operated in the positive ion mode. The derivatization with HMP was very effective at increasing the detectability using the positive-ESI-MS. The method allowed the reproducible and accurate quantification of ng g(-1) tissue levels of prostatic androgens in 10 mg of tissue. That is, the intra- and inter-assay coefficients of variation were below 8.1 and 9.3%, respectively, and the analytical recoveries of the androgens were quantitative. The limits of quantitation for DHT and T were both 1.0 ng g(-1) tissue. The developed method was used to determine DHT and T in the prostates of patients with benign prostatic hyperplasia and prostate cancer, and satisfactory results were obtained.
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: Akinori
authors.initials: A
authors.lastname: Yamauchi
authors.forename: Kazutake
authors.initials: K
authors.lastname: Shimada
authors.forename: Eitetsu
authors.initials: E
authors.lastname: Koh
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizokami
authors.forename: Mikio
authors.initials: M
authors.lastname: Namiki
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D013196:Dihydrotestosterone / Q000032:analysis*; D006801:Humans; D006834:Hydrazines / Q000737:chemistry; D008297:Male; D015394:Molecular Structure; D011470:Prostatic Hyperplasia / Q000473:pathology*; D011725:Pyridines / Q000737:chemistry; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013739:Testosterone / Q000032:analysis*; D013997:Time Factors
chemical_list: C506217:2-hydrazino-1-methylpyridine; D006834:Hydrazines; D011725:Pyridines; D013196:Dihydrotestosterone; D013739:Testosterone