Analysis of lonidamine in rat serum and testis by high performance liquid chromatography

wA HPLC method for the determination of lonidamine in serum and testis, sui table for pharmacological studies in the rat and other mammals, has been de veloped. Briefly, 0.5 mL of serum or about 0.2 g of testicular tissue were extracted with ethyl acetate and evaporated to dryness under nitrogen. The residue was redissolved in methanol and an aliquot was injected onto a C-18 column eluted with a mobile phase consisting of acetonitrile:water (51:49, v/v), containing 0.1% trifluoroacetic acid. The eluate was monitored at 23 0 nm with a sensitivity of 0.05 AUFS. By this method, the pharmacokinetics and the serum and testicular levels of the drug up to 120 h after the admin istration of one single dose (100 mg/kg body weight) of lonidamine to Sprag ue-Dawley rats have been studied. Results were highly variable, as previous ly reported, but a very good Linear correlation was found between the serum and the testicular levels, suggesting that, in the rat, and possibly in th e human, testicular levels could be estimated based on the serum concentrat ions. Copyright (C) 2001 John Wiley & Sons, Ltd.