Automated liquid-liquid extraction method for high-throughput analysis of rosuvastatin in human EDTA K2 plasma by LC-MS/MS

Background: Liquid liquid extraction has been widely used for the analysis of rosuvastatin due to its many attractive features, such as low cost and clean extract. However, manual transfer of the organic phase poses a challenge, particularly when a batch size is large. To overcome the challenge, a simple automated high-throughput (192 samples per batch) liquid liquid extraction method with short (3.0-min) chromatographic run time was proposed. Rosuvastatin was separated using a gradient on a reversed-phase C18 column and detected in the multiple reaction monitoring made with a mass transition of m/z 482.3 -> 4258.2 amu. Results: The assay exhibited a linear range from 50 to 25000 pg/ml (r >= 0.9976). The intra- and inter-day accuracy ranged from 98.16 to 103.84% and 101.18 to 103.95%, respectively. The intra- and inter-day precision ranged from 0.70 to 6.17% and 2.19 to 5.07%, respectively. Conclusion: Finally, the validated method was successfully applied to bioequivalence studies.