8-Aminoquinolines as antimalarial drugs

El-Ashry et al. [36] studied the complex formation between the bromophenol blue, primaquine, and other important aminoquinoline antimalarials. The colorimetric method used was described as simple and rapid and is based on the interaction of the drug base with bromophenol blue to give a stable ion-pair complex. The spectra of the complex show maxima at 415 420 nm with high apparent molar absorptivities. Beer s law was obeyed in the concentration range 1-8,2-10, and 2-12 pg/mL for amodiaquine hydrochloride, primaquine phosphate, and chloroquine phosphate, respectively. The method was applied to the determination of these drugs in certain formulations and the results were favorably comparable to the official methods. 

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