pH indicator titration: a novel fast pKa determination method.

Abstract:

:This study describes a fast spectrophotometic titration method for apparent ionization constant (pKa) determination. In this method, a Universal pH indicator is utilized instead of the conventional pH electrode. An autoburette is set to add HCl at a constant rate to a vigorously stirred 1 cm UV cuvette which contains sample and indicator solution. A spectrophotometer continuously records the spectra. Acquired spectral data are processed by calculating the pH from the indicator spectra in the visible region and extracting sample spectra from the UV region. Five compounds possessing pKa values in the range 2-10 were investigated. These results differed from measurements by conventional spectrophotometric titration by +/-0.05 to +/-0.10 log unit.

journal_name

J Pharm Sci

authors

Kong X,Zhou T,Liu Z,Hider RC

doi

10.1002/jps.20959

subject

Has Abstract

pub_date

2007-10-01 00:00:00

pages

2777-83

issue

10

eissn

0022-3549

issn

1520-6017

pii

S0022-3549(16)32374-7

journal_volume

96

pub_type

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