View More View Less
  • 1 Department of Chemistry and Department of Pharmacology University of Sokoto Nigeria
  • 2 University of Dar-es-Salaam Tanzania
Restricted access

Pharmaceutical intended for use in the tropics are required to maintain their stability under the most severe storage conditions. Chloroquine phosphate, a common antimalarial formulation, was exposed to the sun of the roof top under the extreme heat of the Saharan climate during the hot and dry season (February to June) at an average day temperature of 43°. The heat of meltingΔH determined by differential scanning calorimetry decreased from 60.1 J/g to 33.2 J/g after exposure for 73 days, corresponding to 49% decomposition. Differential scanning calorimetry is shown by this work to be a rapid and reliable technique for the routine quality control of chloroquine phosphate powders and tablet formulations.