title: One-step synthesis of potassium ferricyanide-doped polyaniline nanoparticles for label-free immunosensor.
abstract: A novel, label-free and inherent electroactive redox immunosensor for ultrasensitive detection of carcinoembryonic antigen (CEA) was proposed based on gold nanoparticles (AuNPs) and potassium ferricyanide-doped polyaniline (FC-PANI) nanoparticles. FC-PANI composite was synthesized via oxidative polymerization of aniline, using potassium ferricyanide (K3[Fe(CN)6]) as both oxidant and dopant. FC-PANI acting as the signal indicator was first fixed on a gold electrode (GE) to be the signal layer. Subsequently, the negatively charged AuNPs could be adsorbed on the positively charged FC-PANI modified GE surface by electrostatic adsorption, and then to immobilize CEA antibody (anti-CEA) for the assay of CEA. The CEA concentration was measured through the decrease of amperometric signals in the corresponding specific binding of antigen and antibody. The wide linear range of the immunosensor was from 1.0 pg mL(-1) to 500.0 ng mL(-1) with a low detection limit of 0.1 pg mL(-1) (S/N=3). The proposed method would have a potential application in clinical immunoassays with the properties of facile procedure, stability, high sensitivity and selectivity.
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
authors.forename: Sijing
authors.initials: S
authors.lastname: He
authors.affiliation: The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou 510630, China. Electronic address: 1732259720@qq.com.
authors.forename: Qiyou
authors.initials: Q
authors.lastname: Wang
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Yu
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
authors.forename: Qiujia
authors.initials: Q
authors.lastname: Shi
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China. Electronic address: chenzg@mail.sysu.edu.cn.
authors.forename: Zuanguang
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000814:Aniline Compounds / Q000138:chemical synthesis / Q000737:chemistry; D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D015374:Biosensing Techniques; D002272:Carcinoembryonic Antigen / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D048271:Chitosan / Q000737:chemistry; D005292:Ferricyanides / Q000138:chemical synthesis / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry
chemical_list: D000814:Aniline Compounds; D000906:Antibodies; D002272:Carcinoembryonic Antigen; D005292:Ferricyanides; C416807:polyaniline; D006046:Gold; D048271:Chitosan; C028033:potassium ferricyanide
keywords: Carcinoembryonic antigen; Gold nanoparticles; Label-free immunosensor; One-step synthesis; Potassium ferricyanide-doped polyaniline nanoparticles