Liquid chromatographic determination of the pH-dependent degradation of eseroline--hydrolysis product of physostigmine.
The stability of eseroline, the hydrolysis product of physostigmine under aerobic conditions, was studied by liquid chromatography. A reversed-phase, ion-pair technique was used to separate eseroline from its degradation products. The degradation of eseroline in phosphate buffer solutions of pH 6.91, 7.40, 7.98, 8.41 and 8.94 appears to follow first-order kinetics; the rate constant increased with an increase in pH. The degradation appears to follow specific base catalysis.
Yang
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Department of Pharmacal Sciences, School of Pharmacy, Auburn University, Auburn, AL 36849, USA.
Wilken
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Clark
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