title: Analytical method development and preformulation stability studies of L-665,871 (a beta-agonist) in swine feed.
abstract: An analytical procedure for the determination of the beta-agonist L-665,871 by LC with fluorescence detection has been developed. The mobile phase consists of acetonitrile-phosphate buffer (pH 3.0) with ion-pairing reagent hexanesulphonic acid sodium salt for the analysis of swine feed samples with 1 and 20 microgram g-1 L-665,871. Storage of feed samples at room temperature, however, indicated that the stability L-665,871 and its analogue L-674,239 were greatly compromised by the presence of moisture in the feed. Acidification with maleic acid and/or freezing the feeds were found to significantly improve drug stability.
authors.affiliation: Merck Research Laboratories, Rahway, NJ 07065-0900.
authors.forename: P
authors.initials: P
authors.lastname: DeMontigny
authors.forename: K J
authors.initials: KJ
authors.lastname: Dave
mesh_terms: D000318:Adrenergic beta-Agonists / Q000737:chemistry*; D000631:Aminopyridines / Q000737:chemistry*; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods; D004355:Drug Stability; D004983:Ethanolamines / Q000737:chemistry*; D005453:Fluorescence; D005519:Food Preservation; D006133:Growth Substances / Q000737:chemistry*; D015203:Reproducibility of Results; D013552:Swine; D014867:Water
chemical_list: D000318:Adrenergic beta-Agonists; D000631:Aminopyridines; D004983:Ethanolamines; D006133:Growth Substances; D014867:Water; C085749:L 665871