UNUSUAL INTERFERENCE FROM PRIMARY COLLECTION TUBE IN A HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY ASSAY OF AMIODARONE

We describe an unusual interference in our routine high-performance li quid chromatography (HPLC) assay of amiodarone and its active metaboli te, desethylamiodarone, used to quantify the parent drug and the activ e metabolite in serum from the primary sample collection tube. The int erfering peak had a retention time very similar to that of the authent ic desethylamiodarone. Substitution of Corvac tubes with Vacutainer tu bes for the collection and transportation of serum samples eliminated the source of interference, We routinely suggest the use of Vacutainer collection tubes for obtaining blood samples of cardiac patients unde rgoing amiodarone therapy. (C) 1997 Wiley-Liss, Inc.