A new rapid assay of oestrogens in pregnancy urine using the substrate native fluorescence

Bramhall, John; Britten, A. Z.

doi:10.1016/0009-8981(76)90383-1

Cited by 10 publications

(2 citation statements)

References 14 publications

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“…The FLD k ex and k em values of 280 and 312 nm, respectively, were able to detect both E2-3G and free estrogens, and were close to those reported previously [k ex and k em at 282 and 315 nm, respectively (Mao et al, 2004)] in an analysis of free estrogens E2 and E1. Analyzing 40 ng of E2-3G and E2 produced prominent peaks in the chromatogram; however, the FLD response of E1 at the same mass was low due to its lower native fluorescence (Bramhall and Britten, 1976). A standard injection contained masses of 36.5, 25, and 125 ng for E2-3G, E2, and E1, respectively.…”

Section: Resultsmentioning

confidence: 99%

Radioassay-Based Approach to Investigate Fate and Transformation of Conjugated and Free Estrogens in an Agricultural Soil

Shrestha

Casey

Hakk

et al. 2013

Environmental Engineering Science

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Estrogens, a potent group of endocrine disruptors toward aquatic species, are primarily excreted as conjugates from humans and animals. Radioassay-based approaches with detailed speciation have been frequently conducted for environmental-fate studies for pesticides; however, such techniques have not been exploited for reproductive hormones, and especially for hormone conjugates. This article describes a simple, robust, and highmass-recovery approach to investigate the fate and transformation of a prototype estrogen conjugate, that is, 17b-estradiol-3-glucuronide (E2-3G), and its metabolites (free estrogens) in a laboratory soil and water matrix without the need for enzymatic cleavage and/or fluorescent derivatization. E2-3G and its metabolites were baseline resolved in a single run using high-performance liquid chromatography (HPLC) and quantified by liquid scintillation counting of the HPLC effluents. Transformation of E2-3G and the disposition of its metabolites--the free estrogens 17b-estradiol and estrone--into aqueous, sorbed, and gaseous phases, were adequately accounted for in a soil-water batch system. High mass balances ranging from 99.0% to 114.1% were obtained. Although the method gave lower sensitivity (parts per billion) than tandem mass spectrometer (parts per trillion), it offered sufficient chromatographic resolution and sensitivity to study the fate of labile estrogens in environmental matrices, using the concentration range of this study. An additional advantage of the approach was the relatively low cost of the instrumentation employed. The presented approach can be successfully applied to study the fate of conjugated hormones and their metabolites in the environment allowing simultaneous discernment of complex fate and transformation processes in soil, water, and gas.

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Section: Resultsmentioning

confidence: 99%

Radioassay-Based Approach to Investigate Fate and Transformation of Conjugated and Free Estrogens in an Agricultural Soil

Shrestha

Casey

Hakk

et al. 2013

Environmental Engineering Science

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“…Steroids contain chromophores in their structure, which is why they are UV-absorptive. Still, they show no fluorescent properties, except for estrogens [27]. The steroid structure is dominated by the non-reactive hydroxyl and ketone groups, which is a disadvantage in detecting steroids under highly sensitive methods, e.g.…”

Section: Steroid Analysis and Its Structurementioning

confidence: 99%

Plasma Steroid Level Measured Using Modern Separation Techniques as Biomarkers in Biological Diagnostics

Konieczna¹,

Bączek

2010

CPA

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During the last decade there has been an increased focus on the application of steroids as biomarkers in biomedical practice. The analysis of steroid hormones in biological samples of plasma or serum is currently routinely used in clinical diagnosis being an essential source of information on not only metabolic pathways, but also disorders of the metabolism. More importantly, the steroid hormones may reduce cancer development on the endocrinal basis, reveal abuse of anabolic substances, or even depression incidences. In the case of biomedical research, quantitative determination of steroids in serum or plasma creates an opportunity to diagnose diseases efficiently in their early stages and to monitor a patient for a possible recurrence of a disease after therapy. Therefore, an accurate measurement of steroids in the plasma or serum has become important for the contemporary medicine, even if troublesome especially in view of their low concentration in biological samples.The most common methods of steroid quantification in clinical practice nowadays include immunoassays such as radioimmunoassay or enzyme immunoassay. However, the main disadvantage of the immunoassay techniques consists in cross reactivity of the antibodies used in the assay with the related hormones. On the other hand, there is a number of applications where the analysis is performed with the use of modern separation techniques.The aim of this review is to present the development and applicability of the various analytical methods, all based on separation techniques and used for determination of steroids in the clinical laboratory, taking into account the recent progress in those areas. The review shows the advantages of high-performance liquid chromatography applied to determine non-volatile and thermally labile steroids and steroid conjugates. It also demonstrates that the currently used mass spectrometry offers practically useful structural information on the composition of steroids. A number of techniques and methods are compared and critically discussed pondering finally their specific analytical requirements like sensitivity, specificity, simplicity, limit of detection, and quantification. Nonetheless, plasma or serum sampling seems to remain one of the most convenient methods for population screening purposes.

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Liquid chromatography with fluorometric detection of unconjugated estriol in serum of pregnant women

Kabra

Tsai

Marton

1983

Clinica Chimica Acta

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A new rapid assay of oestrogens in pregnancy urine using the substrate native fluorescence

Cited by 10 publications

References 14 publications

Radioassay-Based Approach to Investigate Fate and Transformation of Conjugated and Free Estrogens in an Agricultural Soil

Radioassay-Based Approach to Investigate Fate and Transformation of Conjugated and Free Estrogens in an Agricultural Soil

Plasma Steroid Level Measured Using Modern Separation Techniques as Biomarkers in Biological Diagnostics

Liquid chromatography with fluorometric detection of unconjugated estriol in serum of pregnant women

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