title: A novel multiplexed fluorescence polarisation immunoassay based on a recombinant bi-specific single-chain diabody for simultaneous detection of fluoroquinolones and sulfonamides in milk.
abstract: Major research efforts are focusing on the development of simultaneous multiplexed immunoassays. In this study, a novel dual-binding fluorescence polarisation immunoassay (DB-FPIA) using a broad-specificity bi-specific single-chain diabody (scDb) and two fluorescent-labelled tracers (sulfamethoxypyridazine-fluorescein isothiocyanate (SMP-FITC) and sarafloxacin-Texas Red (SAR-TR)) with different excitation and emission wavelengths was developed for simultaneous and high-throughput detection of 19 fluoroquinolones (FQs) and 13 sulfonamides (SAs) at the maximum residue limits in milk samples. Recoveries for spiked milk samples were from 76.4% to 128.4%, with a relative standard deviation lower than 13.9%. The developed DB-FPIA was then applied to field samples, followed by confirmation by LC-MS/MS. All three instances in which FQs and SAs were present at concentrations near or above the assay limit of detection were identified as positive by the developed DB-FPIA, demonstrating that the method is suitable for rapid screening of FQs and SAs contamination. The novel methodology combines the advantage of the FPIA and the broad sensitivity of scDb and shows great promise for fast multi-analyte screening of low-molecular weight chemical residues in food samples.
authors.affiliation: a College of Veterinary Medicine , China Agricultural University , Beijing 100193 , China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Kai
authors.initials: K
authors.lastname: Wen
authors.forename: Xiaoqi
authors.initials: X
authors.lastname: Tao
authors.forename: Shuangyang
authors.initials: S
authors.lastname: Ding
authors.forename: Jie
authors.initials: J
authors.lastname: Xie
authors.forename: Xuezhi
authors.initials: X
authors.lastname: Yu
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Li
authors.forename: Xi
authors.initials: X
authors.lastname: Xia
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
authors.forename: Sanlei
authors.initials: S
authors.lastname: Xie
authors.forename: Haiyang
authors.initials: H
authors.lastname: Jiang
mesh_terms: D053000:Analytic Sample Preparation Methods; D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000378:metabolism; D018033:Antibodies, Bispecific / Q000235:genetics / Q000378:metabolism; D000918:Antibody Specificity; D057205:Automation, Laboratory; D002681:China; D004350:Drug Residues / Q000032:analysis* / Q000378:metabolism; D016231:Fluorescence Polarization Immunoassay; D024841:Fluoroquinolones / Q000032:analysis* / Q000378:metabolism; D005506:Food Contamination; D005513:Food Inspection / Q000379:methods*; D017408:Guidelines as Topic; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry* / Q000191:economics / Q000592:standards; D011994:Recombinant Proteins; D015203:Reproducibility of Results; D057127:Single-Chain Antibodies / Q000235:genetics / Q000378:metabolism; D013449:Sulfonamides / Q000032:analysis* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D018033:Antibodies, Bispecific; D024841:Fluoroquinolones; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies; D013449:Sulfonamides
keywords: bi-specific single-chain diabody; fluorescence polarisation; fluoroquinolones; milk; sulfonamides