Simultaneous determination of lamotrigine and monohydroxy-carbazepin in serum by HPLC

AIM To establish a simple and sensitive method for the determination of the concentration of lamotrigine (LTG) and monohydroxy-carbazepin (MHD) in serum by high performance liquid chromatography (HPLC). METHODS The α-bromoacetophenone was used as internal standard. Serum sample was extracted with acetic ether. The analytic column was RP-C18 (SHIMADZU 150 mm × 3.9 mm,5 μm). The mobile phase was methanol ∶ water (50 ∶ 50,V / V) at 1.5 mL·min-1 with UV detection at 254 nm and column temperature was 25 ℃. Sample size was 20 μL. RESULTS A good linearity was shown in the concentration range 1.25 -40 mg·L-1 for LTG,and the range 1.25 -80 mg·L-1 for MHD,and the coefficient of correlation were rLTG = 0.999 1 and rMHD = 0.999 3,the average recovery were (99 ± s 4)% and (96 ± 4)%,respectively. The relative standard deviations of intra-day and inter-day were less than 7%. CONCLUSION The method is simple,sensitive and accurate,and suitable for the determination of MHD and LTG.