High-pressure liquid chromatographic determination of cycloheximide in ointment and suspension formulations

A high-pressure liquid chromatographic procedure is described for the assay of the antibiotic cycloheximidein bulk drug and two experimental formulations. The method utilizes a reversed-phase C18 chromatographic column and refractive index detection. Possible impurities or degradation products, isocycloheximide, anhydrocycloheximide, and dimethylcyclohexone, are well separated from cycloheximide by this procedure. Complete extraction of cycloheximide from the formulations was obtained. The assay has a relative standard deviation of approximately 1%.