title: Poly(o-phenylenediamine)-carried nanogold particles as signal tags for sensitive electrochemical immunoassay of prolactin.
abstract: A novel class of redox-active molecular tags, poly(o-phenylenediamine)-carried nanogold particles (GPPDs), was first synthesized and functionalized with horseradish peroxidase-anti-prolactin conjugates (HRP-anti-PRL). Thereafter, a specific sandwich-type electrochemical immunoassay was designed for determination of prolactin (PRL) by using GPPD-labeled HRP-anti-PRL conjugates as molecular tags on anti-PRL antibody-modified glassy carbon electrode. Compared with pure gold nanoparticles and poly(o-phenylenediamine) microspheres, the as-prepared GPPDs increased the surface coverage of the nanostructures, and enhanced the immobilization amount of biomolecules. Several labeling protocols compromising GPPD-labeled HRP-anti-PRL, nanogold particles-labeled HRP-anti-PRL and poly(o-phenylenediamine) microspheres-labeled HRP-anti-PRL, were investigated for detection of PRL, and improved analytical features were obtained with the GPPD-based strategy. With the GPPD labeling method, dependence of the electrochemical signals on the incubation time and pH of the assay solution were also studied. The strong attachment of HRP-anti-PRL to the GPPDs resulted in a good repeatability and intermediate reproducibility down to 9.8%. The dynamic concentration range spanned from 0.5 to 180 ng mL(-1) PRL with a detection limit of 0.1 ng mL(-1) at the 3S(blank) level. No significant differences at the 95% confidence level were encountered in the analysis of 10 spiked blank cattle serum samples between the developed immunoassay and enzyme-linked immunosorbent assay method for determination of PRL.
authors.affiliation: Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Huafeng
authors.initials: H
authors.lastname: Chen
authors.forename: Yuling
authors.initials: Y
authors.lastname: Cui
authors.forename: Bing
authors.initials: B
authors.lastname: Zhang
authors.forename: Bingqian
authors.initials: B
authors.lastname: Liu
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
authors.forename: Dianping
authors.initials: D
authors.lastname: Tang
mesh_terms: D000818:Animals; D055910:Antibodies, Immobilized / Q000276:immunology; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D055664:Electrochemical Techniques / Q000379:methods; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010655:Phenylenediamines / Q000737:chemistry*; D011388:Prolactin / Q000032:analysis / Q000097:blood* / Q000276:immunology
chemical_list: D055910:Antibodies, Immobilized; D010655:Phenylenediamines; C530487:poly(o-phenylenediamine); D006046:Gold; D011388:Prolactin