title: A label-free electrochemical immunoassay for carcinoembryonic antigen (CEA) based on gold nanoparticles (AuNPs) and nonconductive polymer film.
abstract: A simple and sensitive label-free electrochemical immunoassay electrode for detection of carcinoembryonic antigen (CEA) has been developed. CEA antibody (CEAAb) was covalently attached on glutathione (GSH) monolayer-modified gold nanoparticle (AuNP) and the resulting CEAAb-AuNP bioconjugates were immobilized on Au electrode by electro-copolymerization with o-aminophenol (OAP). Electrochemical impedance spectroscopy and cyclic voltammetry studies demonstrate that the formation of CEA antibody-antigen complexes increases the electron transfer resistance of [Fe(CN)(6)](3-/4-) redox pair at the poly-OAP/CEAAb-AuNP/Au electrode. The use of CEA antibody-AuNP bioconjugates and poly-OAP film could enhance the sensitivity and anti-nonspecific binding of the resulting immunoassay electrode. The preliminary application of poly-OAP/CEAAb-AuNP/Au electrode for detection of CEA was also evaluated.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Hao
authors.initials: H
authors.lastname: Tang
authors.forename: Jinhua
authors.initials: J
authors.lastname: Chen
authors.forename: Lihua
authors.initials: L
authors.lastname: Nie
authors.forename: Yafei
authors.initials: Y
authors.lastname: Kuang
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000276:immunology; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D007118:Immunoassay / Q000379:methods*; D008567:Membranes, Artificial; D008839:Microelectrodes; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D013194:Staining and Labeling
chemical_list: D002272:Carcinoembryonic Antigen; D008567:Membranes, Artificial; D011108:Polymers; D006046:Gold