An isotope dilution gas chromatographic–mass spectrometric method for the simultaneous assay of estrogens and phytoestrogens in urine

Adlercreutz, Herman; Kiuru, Paula; Rasku, Sirpa; Wähälä, Kristiina; Fotsis, Theodore

doi:10.1016/j.jsbmb.2004.10.015

Cited by 40 publications

(33 citation statements)

References 39 publications

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“…Other advances in GC-MS have emphasized the usefulness of stable isotopes for quantitative accuracy, either using isotope-dilution techniques [31] or in vivo labeling [32]. Both methods have great value for comparison of results between laboratories; however, complete in vivo labeling is especially difficult to achieve for animal studies.…”

Section: Advancing Techniques In Gc-msmentioning

confidence: 99%

Extending the breadth of metabolite profiling by gas chromatography coupled to mass spectrometry

Fiehn

2008

TrAC Trends in Analytical Chemistry

208

148

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Gas chromatography coupled to mass spectrometry (GC-MS) is one of the most frequently used tools for profiling primary metabolites. Instruments are mature enough to run large sequences of samples; novel advancements increase the breadth of compounds that can be analyzed, and improved algorithms and databases are employed to capture and utilize biologically relevant information. Around half the published reports on metabolite profiling by GC-MS focus on biological problems rather than on methodological advances. Applications span from comprehensive analysis of volatiles to assessment of metabolic fluxes for bioengineering. Method improvements emphasize extraction procedures, evaluations of quality control of GC-MS in comparison to other techniques and approaches to data processing. Two major challenges remain: rapid annotation of unknown peaks; and, integration of biological background knowledge aiding data interpretation.

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Section: Advancing Techniques In Gc-msmentioning

confidence: 99%

Extending the breadth of metabolite profiling by gas chromatography coupled to mass spectrometry

Fiehn

2008

TrAC Trends in Analytical Chemistry

208

148

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“…250 mL) were collected from a pregnant woman (36 wk, age 35) in 500-mL bottles containing ascorbic acid (0.25 g) that was used for preservation and stored at Ϫ20°C until required for analysis. Because endogenous estrogens and their metabolites excreted in urine are present in glucuronidated (major) and sulfated (minor) forms [13], a hydrolysis step was conducted before SALDI-MS sample preparation. Hydrolysis and extraction were conducted according to the literature [14].…”

Section: Preparation Of Samplesmentioning

confidence: 99%

Determining estrogens using surface-assisted laser desorption/ionization mass spectrometry with silver nanoparticles as the matrix

Chiu

Chang

Chiang

et al. 2008

J. Am. Soc. Mass Spectrom.

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We describe the application of silver nanoparticles (Ag NPs) as matrices for the determination of three estrogens using surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). Because Ag NPs have extremely high absorption coefficients (1.2 x 10(8) M(-1) cm(-1)) at 337 nm, they are effective SALDI matrices when using a nitrogen laser. Three tested estrogens--estrone (E1), estradiol (E2), and estriol (E3)--adsorb weakly onto the surfaces of the Ag NPs, through van der Waals forces. After centrifugation, the concentrated analytes adsorbed on the Ag NPs were subjected directly to SALDI-MS analyses, with the limits of detection for E1, E2, and E3 being 2.23, 0.23, and 2.11 microM, respectively. The shot-to-shot and batch-to-batch variations for the three analytes were less than 9% and 13%, respectively. We validated the practicality of this present approach through the quantitation of E2 in human urine. Using this approach, we determined the concentration of E2 in a sample of a pregnant woman's urine to be 0.16+/-0.05 microM (n=10).

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“…In this method, isofl avonoids were hydrolyzed and measured as free aglycones. This newly-developed immunoassay for IF was compared with GC/MS and HPLC methods to ensure adequate performance in terms of their precision, specifi city and spiking/recovery of added synthetic isofl avones (Adlercreutz et al 2004).…”

Section: Isofl Avone Assessmentmentioning

confidence: 99%

Food matrix and isoflavones bioavailability in early post menopausal women: An European clinical study

Chanteranne

Branca²,

Kaardinal³

et al. 2008

CIA

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Abstract:The estrogenic effects of soy isofl avones (IF) on symptoms of menopause are of particular interest. The aim of the present study was to improve compliance of IF in two IF-enriched foods providing the same IF circulating levels in postmenopausal women. Forty-two healthy postmenopausal women (mean age: 53.28 years) were recruited for a randomized, crossover, multicenter trial conducted in the Netherlands, Italy and France. Over 18 days, volunteers were assigned to two groups and supplemented with two different IF-enriched foods (100 mg IF aglycones/two servings). The fi rst group had to eat two biscuits daily for three days. After a wash-out period (11 d), they received cereal bars for three days. The second group started with the cereal bars and fi nished with biscuits. After IF intake, plasma and urinary levels of genistein, daidzein, O desmethyl angolensin and equol signifi cantly increased and returned to baseline level after the washout period. There was no difference between biscuits and cereals bars intake, as shown by group values at each end of experimental period (day 4 or day 18). Both matrixes are comparable in terms of IF-circulating levels and could be used independently.

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An isotope dilution gas chromatographic–mass spectrometric method for the simultaneous assay of estrogens and phytoestrogens in urine

Cited by 40 publications

References 39 publications

Extending the breadth of metabolite profiling by gas chromatography coupled to mass spectrometry

Extending the breadth of metabolite profiling by gas chromatography coupled to mass spectrometry

Determining estrogens using surface-assisted laser desorption/ionization mass spectrometry with silver nanoparticles as the matrix

Food matrix and isoflavones bioavailability in early post menopausal women: An European clinical study

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