Direct Chiral Resolution of Optical Isomers of Diltiazem Hydrochloride by Packed Column Supercritical Fluid Chromatography

Packed column subcritical and/or supercritical fluid chromatography (p-sub or pSFC) has been used as a powerful chiral separation technique, whereby a mobile phase produces low viscosity, a high diffusion coefficient, and a solvating power. P-sub- or p-SFC tends to obtain higher column efficiency than normal-phase high-performance liquid chromatography (HPLC). Chiral separations using p-sub- or p-SFC, as well as HPLC, have been reported by many researchers, who frequently use columns containing derivatized cellulose packing (1 –10 ).