Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1213530 | Journal of Chromatography B | 2013 | 4 Pages |
Clarithromycin and rifampicin are used for the treatment of Mycobacteria. Pharmacokinetic drug interaction is possibly due to the influence of the two drugs on the liver enzymes. Using a Hypurity Aquastar C18 column (50 mm × 2.1 mm × 5 μm) for liquid chromatography including a polar end-capped phase for the determination of clarithromycin, rifampicin and their metabolites together in plasma using LC–MS/MS resulted in a substantial carry-over. As a consequence, the throughput of the method is not assured. Using a step-by-step troubleshooting procedure, such carry-over was found originating from column memory effect. With the use of another type of C18 column, the carry-over is eliminated. Due to the absence of carry-over, the analytical concentration ranges are extended and are therefore more appropriate for the analysis of patient samples. The method was re-validated for linearity, reproducibility and dilution integrity.
► “Carry-over” of rifampicin and 25 desacetyl rifampicin was originated in the column. ► Replacing the polar end-capped phase column excluded the “carry-over”. ► The new method is more convenience for clinical practice than previous method.