title: Establishment and optimization of monoclonal antibody-based heterologous dcELISA for 19-nortestosterone residue in bovine edible tissue.
abstract: This paper presents the generation of monoclonal antibodies (mAbs) with high specificity against 19-nortestosterone (NT) through cell fusion procedures, and the development of mAb-based heterologous direct competitive enzyme-linked immunoabsorbent assay (dcELISA) methods to detect NT residue using one of these hybridomas (clone 3B8-E6). Under optimal experimental conditions, this assay exhibited a working range of 0.004 to 19 ng/mL with IC₅₀ and limit of detection values of 0.28 and 0.002 ng/mL, respectively, when it was run in 0.01M phosphate-buffered saline (pH 7.4). Except for minor cross-reactivity with β-boldenone (6.9%) and trenbolone (1.2%), other interference to the assay was negligible (<0.05%). No significant differences (P > 0.05) were found for IC₅₀ values when the pH of the assay buffer ranged from 6 to 8 and phosphate ion concentration was less than 20 mM. The dcELISA can tolerate higher concentrations of methanol than other organic solvents tested. When applied to bovine sample, the correlation coefficients (R) of the dcELISA and GC-MS data were 0.9918 in muscle, 0.9834 in liver, and 0.9976 in kidney. Therefore, this assay has the potential to be incorporated into a quantitative monitoring program for the rapid screening of NT residue in food.
authors.affiliation: College of Veterinary Medicine, Northwest A&F University, Yangling, Shanxi, China.
authors.forename: Jinqing
authors.initials: J
authors.lastname: Jiang
authors.forename: Haitang
authors.initials: H
authors.lastname: Zhang
authors.forename: Guangling
authors.initials: G
authors.lastname: Li
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Yang
authors.forename: Renfeng
authors.initials: R
authors.lastname: Li
authors.forename: Ziliang
authors.initials: Z
authors.lastname: Wang
authors.forename: Jianhua
authors.initials: J
authors.lastname: Wang
mesh_terms: D045930:Anabolic Agents / Q000032:analysis*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis; D000918:Antibody Specificity; D001667:Binding, Competitive; D002417:Cattle; D003429:Cross Reactions; D004350:Drug Residues / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005506:Food Contamination; D005513:Food Inspection / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007668:Kidney / Q000737:chemistry; D057230:Limit of Detection; D008099:Liver / Q000737:chemistry; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry; D009277:Nandrolone / Q000032:analysis*; D013739:Testosterone / Q000031:analogs & derivatives / Q000032:analysis; D014204:Trenbolone Acetate / Q000032:analysis
chemical_list: D045930:Anabolic Agents; D000911:Antibodies, Monoclonal; D013739:Testosterone; C013915:boldenone; D009277:Nandrolone; D014204:Trenbolone Acetate