A UPLC-MS/MS method for simultaneous determination of nine antiepileptic drugs in human plasma and its application in TDM.

With the purpose of carrying out therapeutic drug monitoring (TDM) of nine antiepileptic drugs simultaneously in the clinic, a UPLC-MS/MS assay method was developed and validated. Separation of antiepileptic drugs and internal standard (naproxen and diazepam) was performed on an Agilent Eclipse XDB-C column (50.0 × 2.1 mm, 1.7 μm) using water and acetonitrile as mobile phase for gradient elution. Polarity switch ionization mode (positive-negative-positive) was performed in a total run time of 3.0 min. The method validation was conducted based on bioanalytical method validation guidance, including specificity, calibration curve, precision, accuracy, recovery, matrix effect, stability and dilution integrity, and all of the results satisfied the requirements. Consequently, the proposed method was applied to the TDM of nine antiepileptic drugs and was proved to be sensitive, reliable and specific to determine antiepileptic drugs in human plasma simultaneously. Meanwhile, the TDM results showed that the plasma drug concentration of many patients was not within the effective therapeutic range, especially those taking topiramate, oxcarbazepine and levetiracetam, which was of great guiding significance to rational drug use and timely adjustment of the treatment plan. Therefore, individualized therapy based on advanced analytical methods and TDM theory is of great practical significance.