HPLC separation of nadolol and enantiomers on chiralcel OD column

Nadolol (SQ 11725) is a beta-adrenergic blocker which has two chiral centers, this allows for the presence of two racemates known as racemate A (SQ 12181) and racemate B (12182) and a total of four enantiomers. A simple isocratic HPLC method is developed for the separation of nadolol racemate A (SQ 12181) to its corresponding enantiomers RSR-nadolol (SQ 12148) and SRS-nadolol (SQ 12150) and racemate B (SQ 12182) to its corresponding enantiomers RRS-nadolol (SQ 12149) and SSR-nadolol (SQ 12151). Hexane with different percentage of ethanol containing 0.4% diethylamine is used as a mobile phase. The effluents are monitored by ultraviolet detector set at 254 nm. The method showed good efficiency in identification, separation and optical purity determination of nadolol racemates and individual enantiomers in bulk materials and pharmaceutical formulations.