title: High-performance liquid chromatography followed by radioimmunoassay for the determination of a luteinizing hormone-releasing hormone analogue, leuprorelin, and its metabolite.
abstract: A sensitive method for the determination of leuprorelin (TAP-144), a luteinizing hormone-releasing hormone analogue, and its C-terminal metabolite, M-I, in serum and urine has been developed. Leuprorelin and M-I were extracted from serum or urine samples with Sep-Pak C18 cartridges, and separated completely by high-performance liquid chromatography and determined by radioimmunoassay using [125I]leuprorelin as the labelled antigen. The detection limit of the method was 0.05 ng/ml for leuprorelin and M-I, and the recovery of the compounds added to serum and urine was over 88% with a coefficient of variation (within-assay) of less than 5%. The method was applied to the determination of leuprorelin and M-I-like immunoreactivity in serum or urine after administration of once-a-month injectable microspheres of leuprorelin acetate (TAP-144-SR) to patients with prostate cancer.
authors.affiliation: Biology Department, Takeda Analytical Research Laboratories, Ltd., Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ueno
authors.forename: S
authors.initials: S
authors.lastname: Matsuo
mesh_terms: D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000032:analysis* / Q000097:blood / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000032:analysis / Q000097:blood / Q000652:urine; D006801:Humans; D016729:Leuprolide; D008297:Male; D008863:Microspheres; D008969:Molecular Sequence Data; D011471:Prostatic Neoplasms / Q000097:blood / Q000652:urine; D011863:Radioimmunoassay / Q000379:methods*
chemical_list: D000970:Antineoplastic Agents; D007987:Gonadotropin-Releasing Hormone; D016729:Leuprolide