title: Advantages of time-resolved fluorescent nanobeads compared with fluorescent submicrospheres, quantum dots, and colloidal gold as label in lateral flow assays for detection of ractopamine.
abstract: Label selection is a critical factor for improving the sensitivity of lateral flow assay. Time-resolved fluorescent nanobeads, fluorescent submicrospheres, quantum dots, and colloidal gold-based lateral flow assay (TRFN-LFA, FM-LFA, QD-LFA, and CG-LFA) were first systematically compared for the quantitative detection of ractopamine in swine urine based on competitive format. The limits of detection (LOD) of TRFN-LFA, FM-LFA, QD-LFA, and CG-LFA were 7.2, 14.7, 23.6, and 40.1pg/mL in swine urine samples, respectively. The sensitivity of TRFN-LFA was highest. In the quantitative determination of ractopamine (RAC) in swine urine samples, TRFN-LFA exhibited a wide linear range of 5pg/mL to 2500pg/mL with a reliable coefficient of correlation (R2=0.9803). Relatively narrow linear ranges of 10-500pg/mL (FM-LFA) and 25-2500pg/mL (QD-LFA and CG-LFA) were acquired. Approximately 0.005µg of anti-RAC poly antibody (pAb) was used in each TRFN-LFA test strip, whereas 0.02, 0.054, and 0.15µg of pAb were used in each of the FM-LFA, QD-LFA, and CG-LFA test strips, respectively. In addition, TRFN-LFA required the least RAC-BSA antigens and exhibited the shortest detection time compared with the other lateral flow assays. Analysis of the RAC in swine urine samples showed that the result of TRFN-LFA was consistent with that of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and a commercial enzyme-linked immunosorbent assay (ELISA) kit.
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Luo
authors.affiliation: Jiangxi Institute of Veterinary Drug and Feedstuff Control, Nanchang 330047, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xia
authors.affiliation: Jiangxi Institute of Veterinary Drug and Feedstuff Control, Nanchang 330047, China.
authors.forename: Guo-Mao
authors.initials: GM
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Cheng-Hui
authors.initials: CH
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Jiao-Jiao
authors.initials: JJ
authors.lastname: Han
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Gang-Gang
authors.initials: GG
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China. Electronic address: talktolaiwh@163.com.
authors.forename: Wei-Hua
authors.initials: WH
authors.lastname: Lai
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D017979:Gold Colloid / Q000737:chemistry*; D006133:Growth Substances / Q000652:urine*; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods; D057230:Limit of Detection; D010627:Phenethylamines / Q000652:urine*; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D011934:Reagent Strips / Q000032:analysis; D013552:Swine; D053719:Tandem Mass Spectrometry
chemical_list: D005456:Fluorescent Dyes; D017979:Gold Colloid; D006133:Growth Substances; D010627:Phenethylamines; D011934:Reagent Strips; C060897:ractopamine
keywords: Colloidal gold; Fluorescent submicrospheres; Lateral flow assay; Quantum dots; Ractopamine; Time-resolved fluorescent nanobeads