[Direct resolution of clenbuterol enantiomers with amide derivative as chiral stationary phase].

A simple and rapid high performance liquid chromatographic method has been developed for the direct resolution of clenbuterol enantiomers. The method involved the use of an amide type chiral stationary phase(CSP) made of (R)-1-naphthylglycine and 3,5-dinitrobenzoic acid known as the Chirex 3005 column. The effects of different contents of n-hexane, 1,2-dichloroethane and methanol in mobile phase on the chiral separation are discussed. The effects of column temperature and flow rate of mobile phase were also studied. The separation factor obtained was 1.32 and the resolution factor was 1.81 when using the optimized mobile phase composed of n-hexane-1,2-dichloroethane-methanol (54:38:8, volume ratio) at 17 degrees C and 1.0 mL/min. The mechanism of separation is also discussed.