A liquid chromatographic method of suramin has been used for the determination of the polysulfonated naphtylurea in both plasma and plasma filtrate from prostate cancer patients treated with the drug. The chromatographic system is based on the use of tetrabutylammonium bromide as an ion-pairing agent, while UV detection at 237 nm and 313 nm is applied. The sample pretreatment is a simple deproteination step by an organic solvent. The same counter-ion as used in the phase system is added in order to increase the recovery of the almost complete protein-bound suramin. The minimum detectable concentration in plasma is ca. 20 ng/mL at 237 nm, in plasma filtrate 10 ng/mL at 237 nm.
展开▼