Determination of quinocide as impurity in primaquine tablets by capillary zone electrophoresis.
A capillary zone electrophoretic method has been developed and validated for the determination of the impurity quinocide (QC) in the antimalarial drug primaquine (PQ). Different buffer additives such as native cyclodextrins and crown ethers were evaluated. Promising results were obtained when either beta-cyclodextrin (beta-CD) or 18-crown-6 ether (18C6) were used. Their separation conditions such as type of buffer and its pH, buffer additive concentration, applied voltage capillary temperature and injection time were optimized. The use of 18C6 offers slight advantages over beta-CD such as faster elution times and improved resolution. Nevertheless, migration times of less than 5 min and resolution factors (R(s)) in the range of 2-4 were obtained when both additives were used. The method was validated with respect to selectivity, linearity, limits of detection and quantitation, analytical precision (intra- and inter-day variability) and repeatability. Concentrations of 2.12 and 2.71% (w/w) of QC were found in pharmaceutical preparations of PQ from two different manufacturers. A possible mechanism for the successful separation of the isomers is also discussed.
Elbashir
Abdalla A
AA
School of Chemical Sciences, Universiti Sains Malaysia, Penang, Malaysia.
Saad
Bahruddin
B
Ali
Abdussalam Salhin Mohamed
AS
Saleh
Muhammad Idiris
MI
Aboul-Enein
Hassan Y
HY
D000634:Aminoquinolines / Q000032:analysis*; D000962:Antimalarials / Q000737:chemistry*; D043844:Crown Ethers / Q000737:chemistry; D004340:Drug Contamination; D019075:Electrophoresis, Capillary / Q000191:economics / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D011319:Primaquine / Q000737:chemistry*; D012015:Reference Standards; D012680:Sensitivity and Specificity; D013607:Tablets / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D047392:beta-Cyclodextrins / Q000737:chemistry
D000634:Aminoquinolines; D000962:Antimalarials; D043844:Crown Ethers; D013607:Tablets; D047392:beta-Cyclodextrins; C015762:18-crown-6; C010775:quinocide; D011319:Primaquine