Chromatographic and Surfactant Based Potentiometric Determination of Aqueous Dissociation Constant of Mupirocin
Journal
Current Analytical Chemistry
Date Issued
2020-02-11
Author(s)
Karchev, Vasil
DOI
10.2174/1573411014666180704125016
Abstract
<jats:sec>
<jats:title>Background:</jats:title>
<jats:p>The available data concerning aqueous dissociation constant of mupirocin
(sparingly soluble drug) are scarce. In this study, chromatographic, surfactant based potentiometric
concept and spectrophotometric method were used for determination of the aqueous pKa value of
mupirocin.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Methods:</jats:title>
<jats:p>Different approaches were used for estimation of the aqueous pKa value from the apparent
pKa values obtained at four ACN concentrations, ranging from 22% to 30%. The potentiometric determination
of the pKa value of mupirocin was performed using different concentration of Tween 80 as
a surfactant.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Results:</jats:title>
<jats:p>The aqueous pKa value of mupirocin, determined for the first time by reverse-phase liquid
chromatography method, was found to be 4.76. The obtained value was confirmed by potentiometric
method (4.85). It was found that Tween 80 increases the pKa values. The linear relationship between
the apparent pKa values and the surfactant concentrations was used as an approach for estimation
of the aqueous pKa value. Both methods gave similar values for aqueous pKa
which correspond
with the theoretically obtained pKa value (4.88) using Pallas computer program. It was found that
mupirocin gives pH-indipendent spectra, thus spectrophotometric method is not applicable for determination
of pKa of this compound.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Conclusion:</jats:title>
<jats:p>This comprehensive approach used for the pKa determination enable us to obtained reliable
results for the aqueous pKa value of mupirocin. The linear relationship between the pKa values and
the nonionic surfactant concentrations could be used as a reliable and simple approach for determination
of aqueous pKa value of sparingly soluble drugs.</jats:p>
</jats:sec>
<jats:title>Background:</jats:title>
<jats:p>The available data concerning aqueous dissociation constant of mupirocin
(sparingly soluble drug) are scarce. In this study, chromatographic, surfactant based potentiometric
concept and spectrophotometric method were used for determination of the aqueous pKa value of
mupirocin.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Methods:</jats:title>
<jats:p>Different approaches were used for estimation of the aqueous pKa value from the apparent
pKa values obtained at four ACN concentrations, ranging from 22% to 30%. The potentiometric determination
of the pKa value of mupirocin was performed using different concentration of Tween 80 as
a surfactant.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Results:</jats:title>
<jats:p>The aqueous pKa value of mupirocin, determined for the first time by reverse-phase liquid
chromatography method, was found to be 4.76. The obtained value was confirmed by potentiometric
method (4.85). It was found that Tween 80 increases the pKa values. The linear relationship between
the apparent pKa values and the surfactant concentrations was used as an approach for estimation
of the aqueous pKa value. Both methods gave similar values for aqueous pKa
which correspond
with the theoretically obtained pKa value (4.88) using Pallas computer program. It was found that
mupirocin gives pH-indipendent spectra, thus spectrophotometric method is not applicable for determination
of pKa of this compound.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Conclusion:</jats:title>
<jats:p>This comprehensive approach used for the pKa determination enable us to obtained reliable
results for the aqueous pKa value of mupirocin. The linear relationship between the pKa values and
the nonionic surfactant concentrations could be used as a reliable and simple approach for determination
of aqueous pKa value of sparingly soluble drugs.</jats:p>
</jats:sec>