Dell H D, Fiedler J, Jacobi H, Kolle J
Arzneimittelforschung. 1981;31(1):17-21.
Etofenamate in biological specimen can be determined by gas-liquid chromatography with etofenamate benzyl ether as internal standard. Determination in urine is done directly after extraction and concentration, whereas plasma and homogenates from organs have to be prepurified by thin-layer chromatography. Unchanged etofenamate is found in small amounts in human urine (0--4, 6--6, 6--8 h p. appl.). Inflamed rat paws after local application contain up to 75 microgram etofenamate/g in comparison to only 2 microgram flufenamic acid/g tissue. Both compounds are also found in non-inflamed paws, contents being only 3--4% as compared to the inflamed tissue. Elimination of etofenamate from the inflamed area occurs with a half-life of approx. 8.5 h. These results from gas-liquid chromatography correspond to results from t.l.c./fluorescence measurements.
生物样品中的依托芬那酯可用以依托芬那酯苄醚为内标的气液色谱法测定。尿液中的测定在萃取和浓缩后直接进行，而血浆和器官匀浆则必须通过薄层色谱法进行预纯化。人体尿液中发现少量未变化的依托芬那酯（给药后0 - 4、6 - 6、6 - 8小时）。局部应用后，发炎的大鼠爪子中含有高达75微克依托芬那酯/克，而相比之下，每克组织中仅含2微克氟芬那酸。在未发炎的爪子中也发现了这两种化合物，其含量仅为发炎组织的3 - 4%。依托芬那酯从发炎区域的消除半衰期约为8.5小时。这些气液色谱法的结果与薄层色谱/荧光测量的结果一致。
