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2008 | 10 | 1 | 41-44
Article title

Investigations of selected properties of pharmacologically active compounds by chromatographic and potentiometric methods on the chrysin example

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EN
Abstracts
EN
The RP-TLC method was used to determine the dissociation constant of chrysin (5,7-dihydroxyflavone) in methanol-aqueous (1:1 v/v) solutions. In this method the pK value was quantified on the basis of retention data and a retention model. The accuracy of determining the model parameters was analysed using the following statistical criteria: the sum of the squared differences between the experimental and theoretical data, approximation of standard deviation, and the Fisher test. Besides, in this work the potentiometric method was used. Investigations were carried out at ionic strength I=0.1 at T= 298 K. The dissociation constant were determined using the Rossotti method as well as the numerical method based on the procedures of non-linear curve fitting using Microsoft Excel Solver and the user-defined function. It has been found that the differences in the evaluated pK values were relatively small and did not exceed 1.2%.
Publisher
Year
Volume
10
Issue
1
Pages
41-44
Physical description
Dates
published
1 - 1 - 2008
online
3 - 4 - 2008
References
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Document Type
Publication order reference
YADDA identifier
bwmeta1.element.-psjd-doi-10_2478_v10026-008-0010-x
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