DIRECT ENANTIOMERIC SEPARATION OF THE 4 STEREOISOMERS OF NADOLOL USING NORMAL-PHASE AND REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH CHIRALPAK-AD

Two enantiomeric separations have been developed which resolve the fou r stereoisomers of nadolol on Chiralpak AD using high-performance liqu id chromatography. The normal-phase method uses hexane, ethanol and di ethylamine to baseline resolve all four stereoisomers. The reversed-ph ase method uses ethanol, water and diethylamine. Both methods were opt imized by investigating different mobile phase modifiers, flow-rates a nd column temperatures. Accuracy and reproducibility were determined f or quantitating levels of racemate A and racemate B using the normal-p hase method.