Simultaneous determination of three anticon‐vulsants using hydrophilic interaction LC‐MS

A specific and automated method was developed to quantify the anticonvulsants gabapentin, pregabalin and vigabatrin simultaneously in human serum. Samples were prepared with a protein precipitation. The hydrophilic interaction chromatography (HILIC) with a mobile phase gradient was used to divide off ions of the matrix and for separation of the analytes. Four different HILIC‐columns and two different column temperatures were tested. The Tosoh‐Amid column gave the best results: single small peaks. The anticonvulsants were detected in the multiple reaction monitoring mode (MRM) with ESI‐MS‐MS. Using a volume of 100 μL biological sample the lowest point of the standard curve, i.e. the lower LOQs were 312 ng/mL. The described HILIC‐MS‐MS method is suitable for therapeutic drug monitoring and for clinical and pharmcokinetical investigations of the anticonvulsives.