LC and UV Methods for Lamotrigine Determination in Pharmaceutical Formulation

Liquid chromatography (LC) and ultraviolet spectrophotometric (UV) methods for lamotrigine (LTG) determination were validated. The LC separation was achieved on an ACE RP-18 as stationary phase and 0.3% triethylamine in water (v/v) pH 4.0 : methanol (62 : 38, v/v) as mobile phase. Detection was achieved with a photodiode array at 279 nm. The detection response for LTG was linear (r2=0.9999). The specificity and stability were proved using stress conditions. The CV (%) values for intraday and interday precision were less than 2.0%. The method was accurate and robust. The t-student test proved that the LC and UV methods are interchangeable.