Equine Estrone-3-Sulfate ELISA Kit

In this study, the disposable pipette extraction (DPX) approach was employed to prepare water samples containing the hormones 17-beta-estradiol (beta-EST), estrone (ETR), estriol (EST), and 17-alpha-ethinylestradiol (17-EE). Both multivariate and univariate experimental designs were used to optimize the DPX procedure through ultraviolet (UV) and high-performance liquid chromatography (HPLC). The determination of estrogens in water through UV spectroscopy exhibited rank deficiency, and after trying several strategies, it was possible to suggest that the rank deficiency in the spectra was solved by column augmented matrix strategy afterward complexing the hormones with beta-cyclodextrin, in which the relative concentration recovered by the multivariate curve resolution with alternating least squares (MCR-ALS) to each hormone was employed in the development of nonlinear pseudo-univariate calibration models based on support vector machine (SVM) approach. The models were validated through parameters of merit determination and by comparing the models results with those obtained by HPLC. The alternative methodology for the determination of estrogens in water through UV spectroscopy is an environmentally friendly analytical methodology employing less solvent and with high throughput. Moreover, it is not possible to determinate these hormones without using the chemometric approaches, mainly due to the rank deficiency, which needs to be broken to allow for the differentiation between the substances and later modeling.

Phenolic endocrine disrupting chemicals (EDCs) may pose a great hazard to wildlife and humans, owing to their ubiquitous presence in the environment and potential bioaccumulation ability. We investigated the bioaccumulation, metabolism, and human health risks of six phenolic EDCs, including bisphenol A (BPA), 4-tert-octylphenol (4-t-OP), 4-nonylphenol (4-NP), estrone (E1), 17 beta-estradiol (E2), and 17 alpha-ethinylestradiol (EE2), in wild fish from the Pearl River system, South China. Except EE2, the other five EDCs were detected in at least one of the four fish tissues (bile, liver, plasma, and muscle). The concentrations of BPA and 4-NP were greater than those of 4-t-OP, E1, and E2 in all tissues. The median values of log bioaccumulation factors for EDCs at the range of 3.86-4.52 in bile, 2.06-3.16 in liver, 2.69 -3.87 in plasma, and 1.34-2.30 in muscle, indicating a higher bioaccumulation potential in fish bile than in other tissues. Greater levels of glucuronide/sulfate conjugated EDCs were found in fish bile and liver than in the plasma and muscle, suggesting that the liver and bile played an important role in the metabolism and excretion of phenolic EDCs in fish. The calculated hazard quotient values were below 1 for each compound, implying low risk to human health by intake of edible fish. (C) 2019 Elsevier Ltd. All rights reserved.