High-performance liquid and gas chromatographic methods for the determination of cicloprolol.

Two methods, one based on high-performance liquid chromatography (HPLC) and the other on gas chromatography (GC), were developed for the quantification of the partial adrenergic receptor antagonist cicloprolol. In the GC method, samples are cleaned up by back-extraction, then derivatized with heptafluorobutyric anhydride and separated on a capillary cross-linked methylsilicone column. This GC method is time-consuming but, with electron-capture detection, cicloprolol can be quantified at levels down to 1 ng/ml. The HPLC method, using a reversed ODS stationary phase and fluorimetric detection, is less sensitive (5 ng/ml) but, with a single-step extraction, is faster and simpler. The determination of cicloprolol in human blood samples by the two methods gave comparable results. Routine monitoring of cicloprolol can be done easily with the HPLC method, whereas the time-consuming GC method may be reserved for pharmacokinetic studies where late-sampled tubes, with low concentrations, must be analysed.