Sensing estradiol

Conventional ion-selective electrodes have been used as detectors for immunoassays. Antibody binding measurements can be made with hapten-selective electrodes such as the trimethylphenylammonium ion electrode Enzyme immunoassays in which the enzyme label catalyzes the production of a product that is detected by an ion-selective or gas-sensing electrode take advantage of the amplification effect of enzyme catalysis in order to reach lower detection limits. Systems for hepatitis B surface antigen and estradiol use horseradish peroxidase as the enzyme label and... 

Sexual receptivity. The effects of THC on sexual behavior in female rats and its influence on steroid hormone receptors and neurotransmitters in the facilitation of sexual receptivity was examined. Results revealed that the facilitatory effect of THC was inhibited by antagonists to both progesterone and dopamine D(l) receptors. To test further the idea that progesterone receptors (PR) and/or dopamine receptors (D[1]R) in the hypothalamus were required for THC-facilitated sexual behavior in rodents, antisense, and sense oligonucleotides to PR and D(1)R were administered intra-cerebroventricularly into the third cerebral ventricle of ovariectomized, estradiol benzoate-primed rats. Progesterone- and THC-facilitated sexual behavior was inhibited in animals treated with antisense oligonucleotides to PR or to D(1)R. Antagonists to... 

It is probable that other conjugates of steroid hormones and their metabolites will eventually be found to exist in human urine, either as normal or unusual constituents. A conjugate of 17a-estradiol with jS-glucuronic acid and IV-acetylglucosamine has been isolated recently (J3) and an unusual compound, not a conjugate in the usual sense, of urea and... 

Detection of estrone and estradiol in buffer using SPR sensors Biacore 2000 and Biacore 1000 was carried out by Coille et al. [53]. Analyte-BSA conjugates and BSA were immobilized in the sensing and reference channels of a sensor chip, respectively, using NHS-esters. Analyte concentrations detected using inhibition format in this work were in the range 0.01-3000 ngmL ... 

Scheme 5.43 illustrates three applications of this methodology to total synthesis. The first exeunple is taken from Posner s synthesis of estrone and estradiol [211], the second from Posner s synthesis of methyl jasmonate [212], and the third from Holton s synthesis of aphidicolin [213]. The latter is particularly noteworthy in that two contiguous quaternary centers are created in the asymmetric addition with excellent selectivity. In the estrone synthesis, the chirality sense of the product is consistent with the nonchelate model, but the other two examples adhere to a chelate model. Note that the difference is the degree of substitution at the a-position of the enolate. 

Sirotkin, A.V., Makarevich, A.V., M.R. Corkins, Kotwica, J., Kwon, H.B., Bulla, J., and Hetenyi, L. (2001) Secretory Activity of Bovine Ovarian Granulosa Cells Transfected with Sense and Antisense Insulin-Like Growth Factor (IGF) Binding Protein-3 and the Response to IGF-I, GH, LH, Oxytocin and Estradiol, J. Mol. Endocrinol. 27, 329-338. 

Investigations carried out so far on the excretion of endogenous estrogens have not shown any difference between postmenopausal women with and without mammary carcinoma (Brown, 1958). In extensive studies by Bulbrook ei al. (1958a, b, c), the proposition was tested that the clinical course of the disease bears a relation to the excretion of estrone, estradiol-17/3, or estriol. Bulbrook and Strong (1958) reached the conclusion that the studies were negative in the sense that they failed to show a direct relation between the estrogens and the behavior of the disease. 

A fluorescence sensing method based on a combination of HPLC separation and fluorescence detection was developed for the steroid hormone p-estradiol (Fig. 2, 5), which is fluorescent [22]. The imprinted polymer in this system was prepared by the co-polymerization of MAA and EDMA in the presence of the template molecule (Table 1), p-estradiol. This system was able to rapidly and effectively measure p-estradiol concentrations in the range of 0.1-4.0 pM with satisfactory reproducibility. However, this in essence is a HPLC method with the imprinted polymers used as the stationary phase. 

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