title: A competitive immunoassay for ultrasensitive detection of Hg(2+) in water, human serum and urine samples using immunochromatographic test based on surface-enhanced Raman scattering.
abstract: An immunochromatographic test (ICT) strip was developed for ultrasensitive competitive immunoassay of Hg(2+). This strategy was achieved by combining the easy-operation and rapidity of ICT with the high sensitivity of surface-enhanced Raman scattering (SERS). Monoclonal antibody (mAb) against Hg(2+) and Raman active substance 4-mercaptobenzoic acid (MBA) dual labelled gold nanoparticles (GNPs) were prepared as an immunoprobe. The Raman scattering intensity of MBA on the test line of the ICT strip was measured for quantitative determination of Hg(2+). The ICT was able to directly detect Hg(2+) without complexing due to the specific recognition of the mAb with Hg(2+). The IC50 and limit of detection (LOD) of the assay for Hg(2+) detection were 0.12 ng mL(-1) and 0.45 pg mL(-1), respectively. There was no cross-reactivity (CR) of the assay with other nineteen ions and the ICT strips could be kept for 5 weeks without loss of activity. The recoveries of the assay for water, human serum and urine samples spiked with Hg(2+) were in range of 88.3-107.3% with the relative standard deviations (RSD) of 1.5-9.5% (n = 3). The proposed ICT was used for the detection of Hg(2+) in urine samples collected from Occupational Disease Hospital and the results were confirmed by cold-vapor atomic fluorescence spectroscopy (CV-AFS). The assay exhibited high sensitivity, selectivity, stability, precision and accuracy, demonstrating a promising method for the detection of trace amount of Hg(2+) in environmental water samples and biological serum and urine samples.
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China.
authors.forename: Pei
authors.initials: P
authors.lastname: She
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China.
authors.forename: Yanxin
authors.initials: Y
authors.lastname: Chu
authors.affiliation: OptoTrace (Suzhou) Technologies, Inc., STE 316, Building 4, No. 218, Xinghu Street, bioBAY, Suzhou Industrial Park, Suzhou 215123, China.
authors.forename: Chunwei
authors.initials: C
authors.lastname: Liu
authors.affiliation: OptoTrace (Suzhou) Technologies, Inc., STE 316, Building 4, No. 218, Xinghu Street, bioBAY, Suzhou Industrial Park, Suzhou 215123, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Guo
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Zhao
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China. Electronic address: lijgsd@suda.edu.cn.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Li
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China.
authors.forename: Haijing
authors.initials: H
authors.lastname: Du
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: OptoTrace (Suzhou) Technologies, Inc., STE 316, Building 4, No. 218, Xinghu Street, bioBAY, Suzhou Industrial Park, Suzhou 215123, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.affiliation: The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Renai Road 199, Suzhou 215123, China. Electronic address: denganping@suda.edu.cn.
authors.forename: Anping
authors.initials: A
authors.lastname: Deng
mesh_terms: D002846:Chromatography, Affinity; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D014873:Water Pollutants / Q000032:analysis* / Q000097:blood / Q000652:urine
chemical_list: D014873:Water Pollutants
keywords: Colloidal gold nanoparticles; Competitive immunoassay; Immunochromatographic test; Mercury(II) ion; Surface-enhanced Raman scattering