ISOLATION OF ESTRADIOL-17β FROM HEN'S URINE AND ITS CHARACTERIZATION AS THE CRYSTALLINE 3-METHYL ETHER

1965 ◽  
Vol 43 (9) ◽  
pp. 1379-1385 ◽  
Author(s):  
F. Hertelendy ◽  
T. G. Taylor ◽  
R. S. Mathur ◽  
R. H. Common
Keyword(s):  
Melting Point ◽  
Thin Layer ◽  
Methyl Ether ◽  
Crystalline Form ◽  
Crystalline Material ◽  
Chromatographic Behavior ◽  
Estradiol 17Β

Estradiol-17β-3-methyl ether has been prepared in crystalline form from the phenolic steroid fraction of hen's urine and characterized by its melting point, the melting point of its acetate, and the chromatographic behavior of the crystalline material, of its acetate, and of its benzoate in each of three different thin-layer chromatographic systems.The method of Brown has been modified to render it more specific for the determination of estradiol-17β in hen's urine. Values for the estradiol-17β content of the urine of laying and nonlaying hens are reported.

scholarly journals Development of Theoretical Approaches to Determination of the Main Groups of Biologically Active Substances of Medicinal Plant Raw Materials by TLC Method

2021 ◽  
Vol 10 (2) ◽  
pp. 69-79
Author(s):  
O. V. Trineeva
Keyword(s):  
Thin Layer ◽  
Raw Materials ◽  
Biologically Active ◽  
Chromatographic Behavior ◽  
Optimal Conditions ◽  
Plant Origin ◽  
Plant Raw Materials ◽  
Mobile Phases ◽  
Chromatographic Process

Introduction. As is known, the selection of optimal conditions for the analysis of extracts from medicinal plant raw materials (MPМ), as well as medicinal herbal preparations and pharmaceutical substances of plant origin, characterized by a complex variable composition of biologically active substances (BAS) by TLC, presents certain difficulties. For the design of mobile phases for the separation of mixtures of BAS of plant origin, in a thin layer of sorbent, the following approaches are used: literary sources; standard mobile phases; spot elution method; the scheme proposed by the firm Camag (Switzerland); model "PRISMA"; variocameras and others. In foreign literature, there are publications on the generalization of the available experimental data on the determination of various natural groups of BAS in objects of plant origin. However, such reviews did not reveal the regularities of the chromatographic behavior of individual BAS in a thin layer, as well as the influence of various factors on the reproducibility of R f values. The study of the possibility of a theoretical approach to the choice of optimal conditions for chromatography of groups of BAS of different polarity, allowing them to separate, identify and quantify by TLC is a relevant and poorly developed area of chromatography in general.Aim. The aim of this work was to develop a theoretical approach to the choice of optimal conditions for the chromatographic separation of various groups of BAS of plant origin in a thin layer of sorbent.Materials and methods. To study the regularities of chromatographic behavior in a thin layer of representatives of the main classes of BAS present in MPМ (amino acids, flavonoids, tannins, simple sugars, ascorbic acid, fat-soluble vitamins), the value of the main factor affecting the parameters of the efficiency of the chromatographic process, the polarity of the eluent, was studied. As objects of research, we used ready-made chopped raw material of nettle leaves, produced by a domestic manufacturer, that meets the requirements of regulatory documents, as well as sea buckthorn fruits collected on the territory of the Voronezh region, according to the rules for harvesting MPМ of various morphological groups in fresh and dried form.Results and discussion. The regularities of elution and mathematical models describing the chromatographic behavior of plant BAS in a thin layer of sorbent have been established. Based on the totality of the results obtained, from the standpoint of the efficiency of the chromatographic process, the optimal conditions for their TLC analysis were selected and theoretically substantiated. To study the qualitative composition of BAS and to achieve a clear separation of zones on chromatograms, TLC methods were developed and tested on the studied MPМ using simple, frontal or two-dimensional chromatography.Conclusion. It is shown that the determination and separation in a thin layer of the sorbent of hydrophilic and lipophilic BAS of MPМ in the presence of a joint requires different approaches and techniques. The paper proposes an algorithm for the selection of the mobile phase and methods of chromatography of BAS of medicinal products. The revealed mathematical models describing the chromatographic behavior of BAS will make it possible to select the conditions under which it is possible to determine the individual components of multicomponent mixtures without preliminary separation. The developed methods for the determination of BAS can also be used for standardization and quality assessment of other types of MPМ, phytopreparations and pharmaceutical substances of plant origin.

THE CHEMISTRY OF THE "AMINOCHROMES": PART IV. SOME NEW AMINOCHROMES AND THEIR DERIVATIVES

1960 ◽  
Vol 38 (4) ◽  
pp. 516-527 ◽  
Author(s):  
R. A. Heacock ◽  
B. D. Scott
Keyword(s):  
Acetic Anhydride ◽  
Absorption Spectra ◽  
Methyl Ether ◽  
Ethyl Ether ◽  
Crystalline Form ◽  
Chromatographic Behavior ◽  
Visible Absorption

N-Ethylnoradrenochrome, N-isopropylnoradrenochrome, adrenochrome methyl ether, adrenochrome ethyl ether, and their 2-iodo derivatives have been prepared in crystalline form. The action of acetic anhydride in pyridine on these aminochromes has been studied; acetylated rearrangement products were obtained in each case. N-Ethylnoradrenochrome monosemicarbazone, N-ethylnoradrenolutin, 5,6-diacetoxy-N-ethyl-2-iodoindole, and 5,6-diacetoxy-2-iodo-N-isopropylindole have been prepared. The ultraviolet and visible absorption spectra of the aminochromes described above and several 5,6-diacetoxy- and 3,5,6-triacetoxy-N-alkylindoles have been measured and the paper chromatographic behavior of the unhalogenated aminochromes studied.

EINE CHEMISCHE METHODE ZUR BESTIMMUNG VON 16-EPI-ÖSTRIOL IM URIN DES MENSCHEN

1963 ◽  
Vol 44 (1) ◽  
pp. 47-66 ◽  
Author(s):  
W. Nocke ◽  
H. Breuer
Keyword(s):  
Melting Point ◽  
Phosphoric Acid ◽  
Aqueous Alkali ◽  
Percentage Error ◽  
Organic Layer ◽  
Maximum Percentage ◽  
Chemical Determination ◽  
Routine Assay ◽  
Hydrolysis Of

ABSTRACT A method for the chemical determination of 16-epi-oestriol in the urine of nonpregnant women with a qualitative sensitivity of less than 0.5 μg/24 h is described. The separation of 16-epi-oestriol and oestriol is accomplished by converting 16-epi-oestriol into its acetonide, a reaction which is stereoselective for cis-glycols and therefore not undergone by oestriol as a trans-glycol. Following partition between chloroform and aqueous alkali, the acetonide of 16-epi-oestriol is completely separated with the organic layer whereas oestriol as a strong phenol remains in the alkaline phase. 16-epi-oestriol is chromatographed on alumina as the acetonide and determined as a Kober chromogen. This procedure can easily be incorporated into the method of Brown et al. (1957 b) thus making possible the simultaneous routine assay of oestradiol-17β, oestrone, oestriol and 16-epi-oestriol from one sample of urine. The specificity of the method was established by separation of 16-epi-oestriol from nonpregnancy urine as the acetonide, hydrolysis of the acetonide by phosphoric acid, isolation of the free compound by microsublimation and identification by micro melting point, colour reactions and chromatography. The accuracy of the method is given by a mean recovery of 64% for pure crystalline 16-epi-oestriol when added to hydrolysed urine in 5–10 μg amounts. The precision is given by s = 0.24 μg/24 h. For the duplicate determination of 16-epi-oestriol the qualitative sensitivity is 0.44 μg/24 h, the maximum percentage error being ± 100% The quantitative sensitivity (±25% error) is 1.7 μg/24 h.

Development of a method for multielemental determination in water by EDXRF with radioisotopic source of 238Pu.

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Camilo Fuentes Serrano ◽  
Juan Reinaldo Estevez Alvares ◽  
Alfredo Montero Alvarez ◽  
Ivan Pupo Gonzales ◽  
Zahily Herrero Fernandez ◽  
...  
Keyword(s):  
Thin Layer ◽  
Expanded Uncertainty ◽  
Considerable Decrease ◽  
X Ray ◽  
Precipitation Efficiency ◽  
Method Of Determination ◽  
Sensitivity Curves ◽  
Order Of Magnitude ◽  
Metrological Parameters

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238Pu instead of 109Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L).

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