title: Amplified cathodic electrochemiluminescence of luminol based on Pd and Pt nanoparticles and glucose oxidase decorated graphene as trace label for ultrasensitive detection of protein.
abstract: An ultrasensitive electrochemiluminescence (ECL) immunosensor was constructed for ultrasensitive detection of carcinoembryonic antigen (CEA) based on an amplified cathodic ECL of luminol at low potential. Firstly, Au nanoparticles (AuNPs) were electrodeposited onto single walled carbon nanotube-graphene composites (CNTs-Gra) coated glass carbon electrode (GCE) with enhanced surface area and good biocompatibility to capture primary antibody (Ab1) and then bind the antigen analytes. Secondly, Pd and Pt nanoparticles (Pd&PtNPs) decorated reduced graphene oxide (Pd&PtNPs@rGO) and glucose oxidase (GOD) labeled secondary antibody (Pd&PtNPs@ rGO-GOD-Ab2) could be captured onto the electrode surface by a sandwich immunoassay protocol to generate amplified cathodic ECL signals of luminol in the presence of glucose. The Pd&PtNPs@rGO composites and loaded GOD promoted luminol cathodic ECL response by efficiently catalyzing glucose to in-situ produce amount of hydrogen peroxide (H2O2) working as a coreactant of luminol. Then in turn Pd&PtNPs catalyzed H2O2 to generate various reactive oxygen species (ROSs), which accelerated the cathodic ECL reaction of luminol, enhanced the cathodic ECL intensity of luminol and improved the sensitivity of the immunosensor. The as-proposed ECL immunosensor exhibited sensitive response on the detection of CEA ranging from 0.0001 ng mL(-1) to 160 ng mL(-1) with a detection limit of 0.03 pg mL(-1) (S/N=3). Moreover, the stability, specificity, lifetime and reproducibility tests demonstrated the feasibility of the developed immunoassay, which can be further extended to the detection of other disease biomarkers.
authors.affiliation: Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Chongqing 400715, People's Republic of China.
authors.forename: Yaling
authors.initials: Y
authors.lastname: Cao
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Chai
authors.forename: Huijing
authors.initials: H
authors.lastname: Liu
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Liao
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhuo
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000276:immunology; D055664:Electrochemical Techniques; D004566:Electrodes; D005949:Glucose Oxidase / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D049408:Luminescent Agents / Q000737:chemistry; D008163:Luminescent Measurements; D008165:Luminol / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*
chemical_list: D000906:Antibodies; D002272:Carcinoembryonic Antigen; D049408:Luminescent Agents; D010984:Platinum; D008165:Luminol; D010165:Palladium; D006108:Graphite; D005949:Glucose Oxidase