Abstract
An isocratic analytical method based on liquid chromatographic determination with UV detection is described for the determination of isatin in spiked plasma and in its synthetic mixture. The separation of the isatin was achieved on a betasil C-8 column using a mobile phase consisting of a binary mixture of acetonitrile and buffer (Na2CO3 + NaHCO3). The linearity, accuracy and precision were found to be acceptable over the concentration range (5-150 mg/L). LOD and LOQ were found to be 1.09 and 3.3 mg/L, respectively. The developed LC method with UV-visible detection offers simplicity, selectivity, precision and accuracy. It produces a symmetric peak shape and reasonable retention time. No interference was observed with the excipients found in the drug formulation. Forced degradation studies were also conducted on the isatin samples and the results shows that the newly developed method is able to determine the content of isatin in presence of its degradation products. The proposed method when applied to the determination of isatin in spiked plasma samples produced a recovery ranging from 96.0-98.2%.