Abstract
A rapid and sensitive method for the simultaneous gas-chromatographic determination of anticonvulsants (carbamazepin, phenobarbital, primidone and phenytoin) in serum or dried blood spot on filter paper without derivatization is described. The chloroform extract from serum sample is directly injected into a gas-chromatograph equipped with a nitrogen-selective detector, which containes a siliconized glass column, packed with a mixture of 0.25% neopentyl glycolsuccinate polyester-0.025% H3PO4(120cm×3mm I.D.) or a ultrabond 20M (90cm×2mm I.D.). The column temperature and flow rate of carrier gas are 230° and 30ml/min, respectively.
The dried blood spot sample is extracted with a mixture of chloroform-methanol-acetic acid (50: 1: 0.01, by volume). After evaporation of the solvent, the residue is dissolved in chloroform and assayed by the above gas-chromatograph. The recoveries from serum and dried blood spot samples are 87.3-103.3% (n=5) and 86.9-92.4% (n=5), respectively. The determination limit of this method is ing to 5ng Comparison between the results obtained from serum and dried blood spot samples gave a correlation coefficients of 0.97 for phenobarbital, 0.95 for primidone, and 0.88 for phenytoin, respectively. The method proposed here is useful for a routine monitoring for the concentration of drug in blood of patients.
