30808-48-1Relevant articles and documents
High-sensitivity determination of estrogens in fish plasma using chemical derivatization upstream UHPLC–MSMS
Bussy, Ugo,Chung-Davidson, Yu-Wen,Buchinger, Tyler J.,Li, Ke,Li, Weiming
, p. 13 - 19 (2017/05/15)
This article describes the development and validation of a sensitive LC–MSMS method for determination of estrogen in fish plasma. Dansyl chloride derivatization of the phenol functional group in estrogen was used to enhance the response to atmospheric pressure ionization leading to improve the sensitivity. Individual 13C internal standards were selected after comparison with deuterated standards. Liquid-liquid extraction (ethyl acetate or methyl tert-butyl ether) and protein precipitation (acetonitrile, methanol or acetone) were compared for the extraction and clean-up of estrogens from fish plasma. Ethyl acetate was selected as the best alternative with recovery ranging from 61 to 96% and matrix effect ranging from 88 to 106%. Limits of quantification ranged from 0.5 to 1?pg/mL showing a gain in sensitivity of 10,000 times over electrospray ionization of underivatized estrogens. Accuracy and precision were validated over three consecutive days and the method was applied to measure estrogen in sea lamprey (Petromyzon marinus) and lake trout (Salvelinus namaycush) plasma. Estrone and estriol were detected in fish below 1?ng/mL in plasma, justifying the need of a highly sensitive LC–MSMS quantification method.
Simultaneous quantitation of testosterone and estradiol in human cell line (H295R) by liquid chromatography/positive atmospheric pressure photoionization tandem mass spectrometry
Zhang,Rick,Kan,Perala,Geter,Lebaron,Bartels
scheme or table, p. 3123 - 3130 (2012/05/05)
The possible interaction of environmental contaminants with the endocrine system has been an environmental concern since the early 1990s. To examine these interactions test guidelines have been introduced by regulatory agencies to screen for possible endocrine active compounds. One of these guidelines is the EPA's OPPTS 890.1550 [Steroidogenesis (Human Cell Line-H295R)]. This guideline requires the quantification of two major biomarkers (testosterone and estradiol) in various biological test systems. Traditional quantitation methodologies such as Radioimmunoassay (RIA) and Enzyme-linked Immunosorbent Assay (ELISA) have been used to quantify low levels of steroids. However, those methodologies have drawbacks such as the radioactive safety, antibody availability, separate assay for each biomarker, and lack of selectivity. In the current study, a rapid and sensitive liquid chromatography/positive atmospheric pressure photoionization tandem mass spectrometry method (LC/APPI-MS/MS) has been developed and validated for the simultaneous quantitation of testosterone and estradiol in the H295R cell line. Briefly, the media from cultured cells was extracted with dichloromethane (CH2Cl2) containing internal standards of both testosterone-d3 and estradiol-13C3; then, the extracted organic layer was concentrated down to dryness. The final residue was derivatized with dansyl chloride solution, and directly analyzed by LC/APPI-MS/MS. The calibration curves, with concentration ranging from 10 to 2500 pg/mL, were linear with coefficient >0.99. The lower limits of quantitation for both testosterone and estradiol were 10 pg/mL. This method was successfully validated to support requirements of the current EPA Steroidogenesis guideline. This type of method may also provide value for rapid and precise measurements of these two hormones in other in vitro or in vivo test systems.
Effects of room temperature ionic liquids on fluorescence characteristics of 17β-estradiol and its derivative
Wang, Xuedong,Li, Yanyan,Du, Xiwei,Lin, Zhenkun,Huang, Changjiang
scheme or table, p. 1643 - 1648 (2012/06/29)
Previous reports have seldom concerned about the RTILs (Room temperature ionic liquids), and their effects on derivatization reaction or derivatives. In this study, we reported that the effects of four different RTILs, i.e., [EMIM]PF6, [BMIM]PF6, [HMIM]PF6 and [OMIM]PF6, on fluorescence spectra of 17 β-estradiol (E2), and its derivatization solvent dansyl chloride (DNSCl) and the derivative. [BMIM]PF6 had a significant quenching effect on the fluorescence intensity of E2, suggesting the formation of [BMIM]PF6/E2 complexes and possible buried E2 molecular in a more hydrophobic microenvironment. The estimated Stern-Volmer quenching constant (Ksv=0.3519) proved that E2 quenching caused by [BMIM]PF6 was a dynamic quenching process. Four RTILs, with different alkyl chain-length in imidazolium cation, resulted in different quenching intensities to E2 as follows: [EMIM]PF6 > [BMIM]PF 6 > [HMIM]PF6 > [OMIM]PF6. At 5 mg L -1 of DNSCl, [BMIM]PF6, [HMIM]PF6 and [OMIM]PF6 increased the fluorescence intensities of E2 in water by 8.5, 7.6 and 6.1 times, respectively, and a 37-nm hypsochromic shift occurred. The fluorescence intensity for [BMIM]PF6-extracted derivative of E2 increased more than two times compared with that for the control. In conclusion, this study demonstrated that above four hexafluorophosphate salt ionic liquids could be used in derivatization reaction to enhance fluorescent sensitivity in E2 trace residual analysis. Springer Science+Business Media, LLC 2009.
