Extraction, purification and estimation of the androgens and their derivatives

Gower, D. B.

doi:10.1007/978-94-017-3078-5_5

Cited by 4 publications

(2 citation statements)

References 259 publications

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“…However, individual levels of A-S and EpiA-S were not determined, because the antibody showed an equal cross-reactivity to both androgen sulfates (Lewis et al, 1997). Although several determination methods for androgen sulfates, including A-S and/or EpiA-S in biological samples using immunoassay (Bélanger et al, 1994;Zwicker and Rittmaster, 1993;Labrie et al, 1997;Lewis et al, 1997) or gas chromatography-mass spectrometry (Gower, 1995;Shimada et al, 2001) have been reported, they have many problems other than the cross-reactivity for immunoassay, as described above. Most of these are indirect methods requiring chemical or enzymatic hydrolysis of the conjugates, purification by high-performance liquid chromatography and/or a derivatization procedure.…”

Section: Introductionmentioning

confidence: 99%

Determination of sulfates of androsterone and epiandrosterone in human serum using isotope diluted liquid chromatography-electrospray ionization-mass spectrometry

Mitamura¹,

Setaka²,

Shimada³

et al. 2005

Biomed. Chromatogr.

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A promising liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) for analysis of the sulfates of 5α-androgen, androsterone and epiandrosterone (A-S and EpiA-S) in human serum was developed. The method was used to assess one of the markers of 5α-reductase activity of males including patients with prostate cancer (PC). After deproteinization with acetonitrile, the androgen sulfates and the internal standard, [7,7,16, H 4 ]dehydroepiandrosterone-S, were extracted from human serum using a solid-phase extraction cartridge and washed with hexane. The extract was reconstituted and applied to the LC/ESI-MS system operated in the selected ion monitoring mode. The method was validated over the range 0.02-5 µg/mL (A-S) and 0.005-1.5 µg/mL (EpiA-S) using 10 µL of human serum. The method was a concise procedure without chemical or enzymatic hydrolysis of the conjugates, purification by high-performance liquid chromatography and/or derivatization, and proved to be satisfactory in its reproducibility and accuracy. The levels of these androgen sulfates tended to decrease during aging, and the A-S levels in the sera obtained from both healthy males and patients with PC were correlated with their EpiA-S levels.

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Section: Introductionmentioning

confidence: 99%

Determination of sulfates of androsterone and epiandrosterone in human serum using isotope diluted liquid chromatography-electrospray ionization-mass spectrometry

Mitamura¹,

Setaka²,

Shimada³

et al. 2005

Biomed. Chromatogr.

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show abstract

“…Acid hydrolysis at elevated temperatures, which is a more general method that can hydrolyze both glucuronide and sulphate conjugates, has been used for many years to cleave the steroid from its conjugate (17). However, it has two disadvantages: it may alter the structure or the constitution of the steroid and the pigment formed can be taken up in the extract (18).…”

Section: Discussionmentioning

confidence: 99%

Assessment of urinary total testosterone production by a highly sensitive time‐resolved fluorescence immunoassay

Bao

Peng

Shen

et al. 2008

Clinical Laboratory Analysis

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Radioimmunoassay (RIA) that involves purification of the analyte by organic solvent extraction is widely used. Although the extraction RIA is reliable when properly validated, it is time consuming and radioactive, we measure urinary total testosterone with a highly sensitive rapid and accurate time-resolved fluorescence immunoassay (TRFIA) method. High affinity antitestosterone antibody and Eu(3+) labeled Donkey antisheep IgG as tracers were used. The assay was evaluated for specificity, sensitivity, analytical recovery, precision and dilution linearity by the TRFIA method on urine samples. A satisfactory standard curve for testosterone TRFIA has been developed with good sensitivity (5.1 pmol/L). The validity of the assay for urinarytotal testosterone was confirmed by the good correlation between the results obtained by TRFIA (X) and those RIA (Y) (Y=0.075+0.971X, R=0.992). Specificity, analytical recovery, precision and dilution linearity studies were determined and all found to be satisfactory. Male urinary total testosterone excretion ranged from 64.00 to 374.11 nmol/24 hr, which was about four times more than the range for women urinary testosterone excretion (14.16-100.65 nmol/24 hr), which suggests that a direct, reliable, easy to automate, highly sensitive and specific TRFIA type assay for the measurement of total testosterone in urine samples has been developed.

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Simultaneous determination of androstenediol 3-sulfate and dehydroepiandrosterone sulfate in human serum using isotope diluted liquid chromatography–electrospray ionization-mass spectrometry

Mitamura¹,

Nagaoka²,

Shimada³

et al. 2003

Journal of Chromatography B

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Extraction, purification and estimation of the androgens and their derivatives

Cited by 4 publications

References 259 publications

Determination of sulfates of androsterone and epiandrosterone in human serum using isotope diluted liquid chromatography-electrospray ionization-mass spectrometry

Determination of sulfates of androsterone and epiandrosterone in human serum using isotope diluted liquid chromatography-electrospray ionization-mass spectrometry

Assessment of urinary total testosterone production by a highly sensitive time‐resolved fluorescence immunoassay

Simultaneous determination of androstenediol 3-sulfate and dehydroepiandrosterone sulfate in human serum using isotope diluted liquid chromatography–electrospray ionization-mass spectrometry

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