Determination Of Three Antiepileptics in Serum by HPLC Method

Objective To establish a method for determination of antiepileptics in human plasma by HPLC. Method The internal standard method was used, the internal standard method was used to detect the concentration by the area of the cusp between the detection and the internal standard. Use the mobile phase was methanol-water (1:1).The detection wave length was 214 nm, the flow rate was 1.2 ml·min-1 and the temperature of the column was room temperature. The drug of Phenytoin, Phenobarbital and Carbamazepine were internal standard each other. The extraction dose was Tert -Butyl -methylether. Result:In the method of internal standard by HPLC, the minimum limit detection of Phenytoin, Phenobarbital and Carbamazepine were 0.5μg·mL-1, 0.5μg·mL-1 and 0.5μg·mL-1 respectively. The rate of the recovery was nearly 100%, and with good linear relation (r=0.9997, 0.9996 and 0.9998), The relative average recover rate were 96.98%, 97.16% and 96.62%. The average RSD of intra-day were 1.55%, 1.21% and 34%respectively, the average RSD of inter-day were 0.46%, 0.67% and 0.63% respectively. Conclusion: The essay method is simple, sensitive, accurate. The internal standard can decrease the operation error. This essay method is suitable for the determination of Phenytoin, Phenobarbital and Carbamazepine in human plasma and its pharmacokinetic study.