Nature of the Main Contaminant in the Drug Primaquine Diphosphate: GC-MS Analysis

Abstract

In the present work, GC-MS was used to provide evidence on fragmentation differences between primaquine and quinocide. Primaquine and quinocide are readily separated by GC. Both substances give visible M⁺ molecular ion 259 m/z. The base peak in the mass spectrum of primaquine was found to be at m/z 201, in the mass spectrum of the positional-isomer quinocide the base peak was found to be at m/z 187. Two detailed MS fragmentation schemes for primaquine and quinocide are provided which can help to identify primaquine-like derivatives. Using GC-MS, it is possible to recognize with high confidence the positional-isomer contaminant in gas chromatograms of the antimalaria drug primaquine without a standard substance as reference.