title: Screening of danofloxacin residue in bovine tissue by terbium-sensitized luminescence on c18 sorbent strips.
abstract: Danofloxacin (DANO) residue in bovine muscle was screened at 200 ng/g by terbium-sensitized luminescence (TSL) directly measured on 10 × 6 mm C18 sorbent strips. The analyte was first adsorbed on sorbent surface by immersion in defatted homogenates. After reagent application and desiccation, TSL was directly measured on sorbent surfaces at λ(ex) = 273 nm and λ(em) = 546 nm. The luminescence intensity was linearly dependent on DANO concentration in the 0-1000 ng/g range (R(2) = 0.9967). A threshold was established at x(200) - 3σ(200), where x(200) and σ(200) are the mean and standard deviation, respectively, of the DANO signals at 200 ng/g. Among 48 blind samples randomly fortified at 0-1000 ng/g, 45 were screened correctly and 3 negative samples were presumed positive. This simple screening protocol has the potential to significantly reduce sample numbers and hence improve sample throughput and save assay costs.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, United States. chen@ars.usda.gov
authors.forename: Guoying
authors.initials: G
authors.lastname: Chen
authors.forename: Yue
authors.initials: Y
authors.lastname: Du
mesh_terms: D000818:Animals; D002417:Cattle; D004350:Drug Residues / Q000032:analysis*; D024841:Fluoroquinolones / Q000032:analysis*; D007202:Indicators and Reagents; D008163:Luminescent Measurements / Q000379:methods*; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry; D011934:Reagent Strips; D013725:Terbium
chemical_list: D024841:Fluoroquinolones; D007202:Indicators and Reagents; D011934:Reagent Strips; D013725:Terbium; C068581:danofloxacin