PHOTODEGRADATION STUDIES ON CHLOROQUINE PHOSPHATE BY HIGH-PERFORMANCELIQUID-CHROMATOGRAPHY

A method based on high-performance liquid chromatography (HPLC) was de veloped to study degraded chloroquine samples produced after exposure to sunlight in the Sudan. The method was also used to investigate chlo roquine photodegradation after irradiation by UV and sunlight at ambie nt temperature. The study showed that the photodecomposition of chloro quine was pH and solvent dependent. Moreover, the extent of reaction w as found to increase in the absence of oxygen. At pH 8, where the reac tion rate was high, the photodecomposition was found to follow pseudo- first-order reaction kinetics. The HPLC method developed was also empl oyed to analyse chloroquine and its degradation products in two commer cially available brands of chloroquine injections which had been store d under local conditions in the Sudan. A number of degradation product s were separated and examined by photodiode array spectroscopy and pre parative TLC.