Determination of endocrine disruptors in environmental waters using poly(acrylamide-vinylpyridine) monolithic capillary for in-tube solid-phase microextraction coupled to high-performance liquid chromatography with fluorescence detection.

A method for the determination of endocrine disruptors, bisphenol A and 17alpha-ethinylestradiol, in environmental water samples was developed using in-tube solid-phase microextraction followed by liquid chromatography and fluorescence detection. A poly(acrylamide-vinylpyridine) monolithic capillary column was applied as the extraction media in view of its greater phase ratio than open-tubular capillaries and thus higher extraction efficiency. After optimizing the extraction conditions, bisphenol A and 17alpha-ethinylestradiol were extracted directly from water samples in a wide dynamic linear range of 0.5-1000 ng mL(-1), with the detection limits obtained as 0.064 and 0.12 ng mL(-1), respectively. The precision of the method was satisfactory with the intraday and interday RSD values smaller than 7.2%. Environmental water samples of different sources were successfully analyzed with the presented method and the monolithic capillary was proved to be robust and reusable in analyzing real water samples.

Norethynodrel metabolites in human plasma and urine.

PIP: Norethynodrel metabolites in human plasma and urine were analyzed. Samples were collected from healthy young women over 1 24-hour period after the oral administration of 11.1 mg (50 mcCi) of 6, 7-tritiated norethynodrel. The 3 alpha-hydroxy compound from the reduction of the 3-ketone of norethynodrel was the major free metabolite in plasma, with lesser amounts of its 3 beta-isomer and norethindrone. These compounds were identified by carrier addition analysis and their concentrations were estimated by thin-layer radiochromatography. The bulk of plasma metabolites consisted of conjugates and greater than 95% of urinary metabolites (20% of total dose) were conjugated; 2 of which were beta-glucuronides. Enzymatic hydrolysis enabled the urinary compounds to be identified by gas-lizuid chromatography-mass spectrometry. 70-80% (10% of the dose) of the enzymatically hydrolyzed urinary metabolites were hydroxylated compounds. Triols were the principal hydroxylated compounds isolated. The metabolism of norethynodrel was rapid and extensive.^ieng

Collaborative study of the analysis of mestranol in combination with norethindrone or norethynodrel.

PIP: A collaborative study of the analysis of mestranol in combination with norethindrone or norethynodrel by column chromatography and ultraviolet determination is presented. The study consisted of 4 samples which were a commercial norethindrone tablet, a synthetic norethindrone mixture, a commercial norethynodrel tablet, and a synthetic norethynodrel mixture. The samples were analyzed by 13 collaborators. Average mestranol recoveries were 100.4, 99.9, 98.7, and 101.2%, respectively.^ieng

Metabolism of antifertility steroids. I. Norethynodrel.

PIP: The in vivo and in vitro metabolism of norethynodrel was studied in detail, and the configuration and conformation of the major metabolites were established. In both the in vivo and in vitro studies, the initial concentration of the ethynyl steroidal fractions was obtained by using silver nitrate-silica gel columns, further purified with alumina chromatography. Only traces of unchanged norethynodrel were found. The major ethynyl steroidal metabolites from in vitro rabbit liver homogenate studies were isolated in pure form and were found to be idential to the product obtained by reducing norethynodrel with sodium borohydride. Through use of proton nuclear magnetic resonance spectra (NMR) and mass spectra studies, the configurations of the major metabolites of both the in vivo and in vitro systems were identified as 17alpha-ethynyl-3alpha, 17beta-dihydroxy-delta-estrene and 17alpha-ethynyl-3beta, 17beta-dihydroxy-delta-estrene. In humans, both compounds are found as the beta-glucosiduronates in the ratio of 7:3 in favor of the 3alphaisomer. The conformation of the 3alpha-hydroxyl group was shown to be equatorial, while that of the 3beta-epimer was axial.^ieng