Determination Method And In Vivo Metabo Lism Study Of Doxifluridine

Two hundred of doxifluridine was orally administered to 6 Beagle dogs, and blood was serially taken up to 6 hours. The plasma concentration of doxifluridine was measured with a sensitive analytical method validated using LC/MS/MS. The time course of plasma doxifluridine concentration was analyzed with noncompartmental and compartmental approaches.Peak concentration (C_max) was 4.41±2.6μg/ml at 1.17±0.3 hr. The area under the time concentration curve (AUC_6h) was 2.59±1.33μghr/ml,the elimination rate constant and the half-life were 4.16±0.93hr^-1 and 0.19±0.05 hr,respectively.In the model-dependent analysis, one compartment model with first order absorption and excretion with delay described the data best The absorption and elimination rate constants were 3.66±1.19 and 3.72±1.11hr^-1, respectively.The apparent volume of distribution and lag time were estimated as 36.93±26.311 and 0.64±0.20 hr.The results would be worth to conduct a bioequivalence study as well as a pharmacokinetic study of doxifluridine.