title: Ultrasensitive and quantitative detection of a new β-agonist phenylethanolamine A by a novel immunochromatographic assay based on surface-enhanced Raman scattering (SERS).
abstract: Phenylethanolamine A (PA) is a new kind of β-agonist, which was illegally used as a feed additive for growth promotion in China. In this study, a novel immunochromatographic assay (ICA) based on surface-enhanced Raman scattering (SERS) for the ultrasensitive and quantitative detection of phenylethanolamine A is presented. The principle of this new ICA is similar to that based on colloidal gold particles, but using Au(MBA)@Ag-Ab [e.g., polyclonal antibody of PA labeled Au@Ag core-shell nanoparticles (NPs) sandwiched with a Raman reporter (4-mercaptobenzoic acid, MBA)] as a probe. After ICA procedures, the specific Raman scattering intensity of MBA on the test line was measured for quantitative detection of PA. This assay was completed within 15 min. The IC50 and limit of detection (LOD) values of the ICA for PA detection were 0.06 ng mL(-1) and 0.32 pg mL(-1), respectively, which were 1-3 orders of magnitude lower than those obtained by other immunoassays, indicating the ultrasensitivity of this ICA. There was no cross-reactivity (CR) of the assay with another three β-agonists (ractopamine, clenbuterol, and salbutamol), suggesting high specificity of the SERS-based ICA. A spiking experiment revealed that the recoveries of PA from pig urine samples were in range of 99.9- 101.2% with relative standard deviations (RSDs) of 3.6-5.8%. The results demonstrated that this SERS-based ICA was able to quantitatively detect PA in urine samples with high sensitivity, specificity, precision, and accuracy and might be a powerful method for the analysis of other target analytes in the food area.
authors.affiliation: The Key Laboratory of Health Chemistry and Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering and Materials Science, and ‡College of Pharmacy Sciences, Soochow University , Suzhou 215123, China.
authors.forename: Mingxin
authors.initials: M
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
authors.forename: Shuqun
authors.initials: S
authors.lastname: Li
authors.forename: Kang
authors.initials: K
authors.lastname: Zhao
authors.forename: Jianguo
authors.initials: J
authors.lastname: Li
authors.forename: Danni
authors.initials: D
authors.lastname: Jiang
authors.forename: Lulu
authors.initials: L
authors.lastname: Sun
authors.forename: Anping
authors.initials: A
authors.lastname: Deng
mesh_terms: D015078:2-Hydroxyphenethylamine / Q000032:analysis* / Q000652:urine; D000318:Adrenergic beta-Agonists / Q000032:analysis* / Q000652:urine; D000818:Animals; D002846:Chromatography, Affinity / Q000295:instrumentation / Q000379:methods*; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D012680:Sensitivity and Specificity; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013552:Swine
chemical_list: D000318:Adrenergic beta-Agonists; D006046:Gold; D015078:2-Hydroxyphenethylamine
keywords: Raman reporter; antibody; core−shell nanoparticles; immunochromatographic assay (ICA); phenylethanolamine A; surface-enhanced Raman scattering (SERS)