Development of a Sensitive and Stereoselective HPLC Method for the Analysis of Pindolol in Plasma and Pharmaceutical Products Using a Chiralpak IB Column and Fluorescence Detection

A sensitive and stereoselective HPLC method has been developed for the simultaneous determination of pindolol enantiomers in plasma and pharmaceutical products. Enantiomeric resolution was achieved on a cellulose tris(3,5-dimethylphenylcarbamate) immobilized onto a 5 μm spherical porous silica chiral stationary phase (CSP) known as Chiralpak IB with fluorescence detection set at 266 nm for excitation and 308 nm for emission. The mobile phase consists of n-hexane–isopropanol–triethylamine, (50:50:0.5), (v/v/v) has been used at a flow rate of 1.0 ml/min. The method was highly specific where other coformulated drugs such as clopamide and isosorbide did not interfere. The stability of pindolol enantiomers under different degrees of temperature was studied. The method validated for its linearity, accuracy, precision and robustness. There was no significant difference (p>0.05) between inter- and intra-day studies for each enantiomers which confirmed the reproducibility of the assay method. Preliminary data suggest that S-(−)-pindolol induces less bradycardia but more sedation and central nervous system depression than racemic pindolol.