Performance comparison between packed column supercritical fluid chromatography (SFC) and HPLC using cyclandelate as the model analyte

A reproducible and fast method has been developed for the assay of cyclandelate in bulk and drug forms using packed column supercritical fluid chromatography using dicyclohexyl phthalate (DCHP) as internal standard. The drug and the internal standard were resolved by elution with supercritical fluid carbon dioxide doped with 14.29% (v/v) methanol on an RP-C₁₈ column and detected spectrophotometrically at 228 nm. Chromatographic figures of merit using C₈, C₁₈, cyano and phenyl columns have been assessed. Parallel experiments have been performed by HPLC and the data have been compared. Supercritical fluid extraction using CO₂ modified with a small amount of methanol was found to give quantitative analytical recoveries of cyclandelate from a dosage form. SFC has been shown to be a viable, faster alternative technique to HPLC generating less disposable waste. Received: 20 June 1997 / Revised: 20 October 1997 / Accepted: 26 October 1997