title: Nanogold-enwrapped graphene nanocomposites as trace labels for sensitivity enhancement of electrochemical immunosensors in clinical immunoassays: Carcinoembryonic antigen as a model.
abstract: A new, highly sensitive electrochemical immunosensor with a sandwich-type immunoassay format was designed to quantify carcinoembryonic antigen (CEA), as a model tumor marker, using nanogold-enwrapped graphene nanocomposites (NGGNs) as trace labels in clinical immunoassays. The device consisted of a glassy carbon electrode coated with Prussian Blue (PB) on whose surface gold nanoparticles were electrochemically deposited to the further modified with the specific analyte-capturing molecule, anti-CEA antibodies. The immunoassay was performed using horseradish peroxidase (HRP)-conjugated anti-CEA as secondary antibodies attached on the NGGN surface (HRP-anti-CEA-NGGN). The method using HRP-anti-CEA-NGGNs as detection antibodies shows high signal amplification, and exhibits a dynamic working range of 0.05-350 ng/mL with a low detection limit of 0.01 ng/mL CEA (at 3s). The assayed results of serum samples with the sensor received an acceptable agreement with the reference values. Importantly, the methodology provides a promising ultrasensitive assay strategy for clinical applications.
authors.affiliation: Department of Cancer Center, Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing 400042, PR China.
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Zhong
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Jinlu
authors.initials: J
authors.lastname: Shan
authors.forename: Yi
authors.initials: Y
authors.lastname: Qing
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D015374:Biosensing Techniques / Q000295:instrumentation*; D002272:Carcinoembryonic Antigen / Q000032:analysis*; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D007118:Immunoassay / Q000295:instrumentation*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000379:methods
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D020099:Coated Materials, Biocompatible; D006108:Graphite