Comparison of enzyme immunoassay and high-performance liquid chromatography determination of carbamazepine in human serum.

The sera (if 40 patients treated with carbamazepine were analyzed by enzyme immunoassay (EMIT) and high-performance liquid chromatograph. (HPLC) and t he results were compared. The chromatographic method includes carbamazepine extraction with methylene chloride anti its chromatographic separation in a Nova Pak Ct, column by using a mixture of 25% v/v acetonitrile in H2O pH 5.6. Detection was made in an absorbance detector at 215 nm. Correlation between these two methods xas 0.93. Confidence hands for predic ting H PLC according to the EMIT with Working-Hotelling criterium showed 1. 1, 0.5 and 1.6 mug/ml maximun error at low, medium and high ranges, respect ively with a p=0.05 probability. The equation expressing the behavior of carbamazepine measurement by HPLC i n function of EMIT is as follows: HPLC=0.824 x EMIT + 0.777 Afterwards, the chromatographic method was used for determining the serum p redosis levels of carbamacepine and 10, 11-epoxi-carbamacepine in five epil eptic patients that received an oral dosis of 200 mg of carbamacepine every 8 hrs as the only anticonvulsivant for controlling their crises.