title: Reversed-phase liquid chromatography of radiolabeled peptides using a C18 guard-PAK precolumn system.
abstract: In order to avoid radioactive contamination of high-performance liquid chromatography columns and injectors, we have investigated the use of a Guard-PAK precolumn system for the chromatography of [125I] labeled peptides. Two gonadotropin-releasing hormone analogs: 1) [D-Ala6-des-Gly10]-GnRH (GnRH-[Ala6]) and 2) [D-Ser(TBu)6-des-Gly10]-GnRH (GnRH-[Ser6]) and rat prolactin (r-PRL) were radiolabeled with 125I and subjected to reversed-phase liquid chromatography using a C18 Guard-PAK precolumn system. Major peak fractions of purified [125I]GnRH-[Ala6], [125I]GnRH-[Ser6], and [125I]r-PRL eluted at 24%, 28%, and 55% acetonitrile, respectively. Purified [125I]GnRH analogs showed specific high affinity binding to rat anterior pituitary gland membranes (specific activity: 1500-1700 Ci/mmol). Purified [125I]r-PRL showed high affinity binding to r-PRL antibody by RIA (specific activity: 70-75 microCi/micrograms). This rapid and efficient chromatographic method should be useful in the separation of a wide range of radiolabeled protein and peptide molecules.
authors.affiliation: Endocrine Laboratory, McGill University, Montreal, Quebec, Canada.
authors.forename: P D
authors.initials: PD
authors.lastname: Carrière
authors.forename: H P
authors.initials: HP
authors.lastname: Bennett
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000302:isolation & purification*; D007457:Iodine Radioisotopes; D011388:Prolactin / Q000302:isolation & purification*; D051381:Rats
chemical_list: D007457:Iodine Radioisotopes; D007987:Gonadotropin-Releasing Hormone; D011388:Prolactin