Manual and automatic extraction and high-performance liquid chromatographic determination of a spicamycin derivative, KRN5500, in rat plasma.

A sensitive reliable method for the extraction, separation and quantitation of KRN5500 (I), a spicamycin derivative, from rat plasma was developed. It involves solid-phase extraction of the drug using a Bond Elut C18 cartridge and reversed-phase HPLC on a YMC-Pack ODS column with an ultraviolet detector. The intra- and inter-assay coefficients of variation by manual (n=10) and automatic (n=5) extraction were less than 9 and 13% and 6 and 8%, respectively. The limit of quantitation of each extraction procedure was 2 ng potency/ml. This extraction method may thus be considered useful for monitoring I in animals following its administration.