Determination of fenticonazole and its impurities by capillary electrophoresis and high performance liquid chromatography

Fenticonazole, a topical antifungal agent containing a stereogenic centre, is used in therapy as a racemic mixture. Five related compounds can be foun d as impurities in the drug. We propose a HPLC method using as stationary p hase a RP-8 column eluted with different gradients of acetonitrile/phosphat e buffer (pH 6) for simultaneous determination of the drug and these impuri ties. We also studied a high performance capillary electrophoresis (HPCE) m ethod for quality control of fenticonazole. The separation of fenticonazole from all its impurities by HPCE was obtained in a relative short capillary (40 cm, effective length 34 cm, 50 mum ID) with a running buffer of 30mM p hosphate (pH3) containing 8mM trimethyl-beta -cyclodextrin. Under these exp erimental conditions very good separation of fenticonazole from each indivi dual impurity is obtained in less than 20 minutes. The choice of cyclodextr in added to the running buffer was dictated by the chiral nature of fentico nazole; trimethyl-beta -cyclodextrin is mainly used as chiral selector. The optimised HPLC and HPCE methods are compared.