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 Scijournal_title
Journal of pharmaceutical sciencesauthors
Kong X,Zhou T,Liu Z,Hider RCdoi
10.1002/jps.20959subject
Has Abstractpub_date
2007-10-01 00:00:00pages
2777-83issue
10eissn
0022-3549issn
1520-6017pii
S0022-3549(16)32374-7journal_volume
96pub_type
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