Simple, rapid and highly sensitive HPLC method for measurement of Lamotrigine in human plasma and its clinical applications

Abstract

Spikes in Lamotrigine concentrations levels and associated clinical toxicity may occur unpredictably. This study describes the development and validation of a simple, more rapid, highly sensitive and economical method for measuring Lamotrigine (LTG) concentration levels in human plasma using HPLC-UV and its clinical applications. Analyte from plasma was extracted with methanol (protein precipitation) and separated on the analytical column Diamonsil C₁₈ (150mm×4.6mm, 5μm) Waters-Milford, MA, United States. Mixture of 0.1% Trifluoroacetate and Methanol used as mobile phase in a 59:41 volume/volume mixture with an isocratic flow rate of 1.5 ml/min and wavelength was adjusted to 260nm. Standard curve of lamotrigine showed good linearity over the range of 1.0-50μg/mL (r²=0.9961) and LLOQ was 1.0μg/ml. The Specificity, Recovery, Accuracy, Stability, Robustness and RSDs for both intraday and interday precision were within acceptable limits. The highly sensitive HPLC assay for determination of LTG in human plasma was demonstrated, validated and applied in Therapeutic Drug Monitoring (TDM) of sixty seven epilepsy patients who were using LTG. The proposed method can be easily applied in routine Therapeutic monitoring of LTG, Besides TDM, stated method can be also very useful for Bioequivalence studies, Pharmacovigilance and Pharmacokinetics studies.