Kinetics of camptothecin deactivation determined by time evolution of fluorescence and absorption spectra

摘要

Fluorescence and absorption spectra of camptothecin - anticancer alkaloid, are analysed in this paper. Camptothecin exists in two forms: lactone and carboxylate. Only lactone form is biologically active. In physiological fluids at pH 7.4 lactone form hydrolyses and converts into carboxylate form. There are some differences in shapes between fluorescence and absorption spectra of lactone and carboxylate form. In the deactivation process fluorescence and absorption spectra evaluate. Thanks to the factor analysis of series of spectra recorded during the process of hydrolysis one can follow the concentration of both forms in the solution. Described method could be useful in determining of kinetics of deactivation process and competitive with the HPLC method.