Principles and Practice of Chromatography - Chromatography Applications > Liquid Chromatography Applications > Analysis of β-blockers > Page 90

CHIRACEL OD-R (a cellulose carbamate) and CHIRACEL OJ-R (a cellulose ester) were used as stationary phases to separate the individual enantiomers. The enantiomers of the DBDPro were well separated on the CHIRACEL OD-R column. However, the DBDMet enantiomers could not be separated on the CHIRACEL OD-R column but were well separated on the CHIRACEL OJ- R column as were the DBDAte isomers. The separation of the DBDMet and DBDAte isomers are shown in figure 49 (chromatogram A, DBDMet and chromatogram B, DBDAte). Each enantiomeric pair represents 50 pmol of the original drug. The separation was carried out on the CHIRACEL OJ-R column (15 cm long, 4.6 mm I.D., packed with particles 5 mm in diameter coated with the cellulose ester. The mobile phase used for the separation of DBDMet was methanol/acetonitrile : 90/10 v/v, at a flow rate of 0.5 ml/min., the separation ratio was 1.33. The mobile phase used for the separation of DBDAte was methanol, also at a flow rate of 0.5 ml/min., the separation ratio being 1.53. The excitation wavelength was 450 nm and the emission wavelength was 560 nm. The fluorescent derivatives were found to be stable at 4˚C for over 1 week.

Courtesy of the Royal society of Chemistry, Ref. [12]

 

Figure 49 The Separation of Derivatized Metoprolol and Atenolol at High Sensitivity