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

• Authors: Janusz Pusz , Wojciech Zapała , Bogdan Papciak
• Languages of publication: 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%.

Keywords

EN

RP-HPLC; retention model; chrysin; dissociation constant

• Publisher: De Gruyter Open
• Journal: Polish Journal of Chemical Technology
• Year: 2008
• Volume: 10
• Issue: 1
• Pages: 41-44

Dates

published

1 - 1 - 2008

online

3 - 4 - 2008

Contributors

author

Janusz Pusz

• Department of Inorganic and Analytical Chemistry

author

Wojciech Zapała

• Department of Chemical and Process Engineering, Chemical Faculty, Rzeszów University of Technology, Powstańców Warszawy 6, 35-959 Rzeszów, Poland

author

Bogdan Papciak

• Department of Inorganic and Analytical Chemistry

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Identifiers

DOI

10.2478/v10026-008-0010-x