Development and full validation of an innovative HPLC-diode array detection technique to simultaneously quantify lacosamide, levetiracetam and zonisamide in human plasma

Aim: To implement pharmacokinetic drug monitoring and individualize the posology of new antiepileptic drugs, the first HPLC-diode array detection method was developed and validated to simultaneously quantify lacosamide, levetiracetam and zonisamide in human plasma. Materials & methods: Preceded by a reproducible liquid-liquid extraction, chromatographic separation was achieved by using a C-18 column of 5 cm length and a mobile phase of water/acetonitrile. Full validation was performed according to in- ternational guidelines. Results: The method was linear within 0.5-30, 2.5-40.0 and 0.5-50.0 mu g ml(-1) for lacosamide, levetiracetam and zonisamide, respectively (r(2) >= 0.998), accurate (-12.411-8.303%), precise (<= 8.875%). Conclusion: This innovative HPLC-diode array detection method was successfully employed in clinical practice and is expected to empower epileptic patients with a personalized pharmacotherapy service. [GRAPHICS] .