Quantification of Lamotrigine in Human Serum by High-Performance Thin-Layer Chromatography

An HPTLC method with densitometric detection at 280 nm has been established for quantification of lamotrigine in human serum. Liquid-liquid extraction with ethyl acetate, with chloramphenicol as internal standard, was followed by chromatography on silica gel F254 plates with ethyl acetate-methanol-32% aqueous ammonia 17:2:1 (v/v) as mobile phase. The method was validated for linearity, precision, and accuracy. Calibration plots were linear in the range 0.6 to 300 ng per band, corresponding to 0.06–30.00 ng µL−1 lamotrigine in human serum after extraction and application of 1 µL to the chromatographic plate. The correlation coefficient was 0.998. Intra-assay and inter-assay precision, as relative standard deviation (RSD), were in the range 0.53–2.91% (n = 3) and 1.58–2.98% (n = 9), respectively. The limits of detection and quantification were 0.016 and 0.042 ng, respectively. Accuracy, calculated as percentage recovery, was between 94.09 and 101.30%, with RSD no higher than 3.52%. The method was selective for both lamotrigine and the internal standard. The method enables rapid, precise, accurate, selective, and sensitive quantitative analysis of lamotrigine in human serum.