title: Amperometric immunosensor for simultaneous detection of three analytes in one interface using dual functionalized graphene sheets integrated with redox-probes as tracer matrixes.
abstract: A novel immunoassay protocol for simultaneous electrochemical determination of alpha-fetoprotein (AFP), carcinoembryonic (CEA) and streptococcus suis serotype 2 (SS2) was designed. As standard sandwich-type immunoassay format, three primary antibodies (Ab1), anti-CEA and anti-AFP and anti-SS2, were immobilized via protein A (PA) adsorbed by Nafion modified electrodes, and functionalized graphene sheets (GS), containing abundant gold nanoparticles (AuNPs) and carboxyl group, were used to immobilize secondary antibody@redox-probe so as to act as tracer. Concentration of each analyte was quantitatively related to the reduction peak current of corresponding redox-probe in differential pulse voltammetry (DPV) scan. The resulting immunosensor exhibited high selectivity and sensitivity in simultaneous determination of three analytes. The linear range was from 0.016 to 50 ng/mL for AFP with a detection limit of 5.4 pg/mL, 0.010 to 50 ng/mL for CEA with a detection limit of 2.8 pg/mL and 0.012 to 50 ng/mL for SS2 with a detection limit of 4.2 pg/mL (S/N=3).
authors: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. 21447388@qq.com
authors: Qiang
authors: Q
authors: Zhu
authors: Yaqin
authors: Y
authors: Chai
authors: Ruo
authors: R
authors: Yuan
authors: Ying
authors: Y
authors: Zhuo
authors: Jing
authors: J
authors: Han
authors: Ya
authors: Y
authors: Li
authors: Ni
authors: N
authors: Liao
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D045424:Complex Mixtures / Q000032:analysis*; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation*; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D010084:Oxidation-Reduction; D018511:Systems Integration
chemical_list: D045424:Complex Mixtures