Résumé
Objective To establish a sensitiv e and specific LC-MS/MS method for the simultaneous determination of cefoperazone and sulbactam in plasma and ultrafiltrate of patients undergone continuous renal replacement therapy(CRRT). Methods Cefuroxime axetil was used as the internal standard,the plasma samples were separated on an WatersAtlantis dC18 column (150 mm× 4.6 mm, 5.0 μm). A tandem mass spectrometer equipped with ESI was used as the detector and operated in the mode of multiple reaction monitoring.Quantitive analysis of[M-H]-ions were m/z 644.1→528.1(cefoperazone), m/z 231.8→188.0(sulbactam) and m/z 509.3→206.9(the internal standard, IS), respectively. Results The linear range of cefoperazone and sulbactam in human plasma and ultrafiltrate were(10-500) and(6-300)μg/ml, respectively. Extraction recoveries were more than 90.0%, and intra- and inter-day relative standard deviation was less than 15%. The matrix effect of plasma and ultrafiltrate showed that the matrix effect of the two media had little influence on the measurement of cefoperazone, sulbactam and IS. Conclusion The method is simple, fast, and highly sensitive. The two drugs can be detected simultaneously in the same sample. It is appropriate to monitor drug concentration in plasma and ultrafiltrate of the patients undergone CRRT. Sieving coefficient could be calculated and provide an accurate basis for dose adjustment.