Electrochemiluminescence of luminol enhanced by the synergetic catalysis of hemin and silver nanoparticles for sensitive protein detection

• Published in: Biosensors & bioelectronics Vol. 54; pp. 20 - 26
• Main Authors: Jiang, Xinya, Chai, Yaqin, Wang, Haijun, Yuan, Ruo
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.04.2014; Elsevier
• Subjects: Biological and medical sciences; Biosensing Techniques; Biotechnology; Carcinoembryonic Antigen - analysis; Catalysis; Electrochemical Techniques - methods; Electrochemiluminescence; Fundamental and applied biological sciences. Psychology; Glucose oxidase; Glucose Oxidase - metabolism; Graphene; Graphite - chemistry; Hemin; Hemin - chemistry; Humans; Hydrogen Peroxide - metabolism; Limit of Detection; Luminescent Agents - chemistry; Luminescent Measurements - methods; Luminol; Luminol - chemistry; Nanoparticles; Nanoparticles - chemistry; Silver - chemistry; Nanoparticles; Glucose oxidase; Hemin; Electrochemiluminescence; Graphene; Luminol; Enzyme; Nanoparticle; Protein; Silver; Oxidoreductases; Catalysis; Detection
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2013.10.006

A novel and ultrasensitive electrochemiluminescence (ECL) immunosensor, which was based on the amplifying ECL of luminol by hemin-reduced graphene oxide (hemin-rGO) and Ag nanoparticles (AgNPs) decorated reduced graphene oxide (Ag-rGO), was constructed for the detection of carcinoembryonic antigen (CEA). For this proposed sandwich-type ECL immunosensor, Au nanoparticles electrodeposited (DpAu) onto hemin-rGO (DpAu/hemin-rGO) constructed the base of the immunosensor. DpAu had outstanding electrical conductivity to promote the electron transfer at the electrode interface and had good biocompatibility to load large amounts of primary antibody (Ab1), which provided an excellent platform for this immunosensor. Moreover, AgNPs and glucose oxidase (GOD) functionalized graphene labeled secondary antibody (Ag-rGO–Ab2–GOD) was designed as the signal probe for the sandwiched immunosensor. Not only did the hemin-rGO improve the electron transfer of the electrode surface, but hemin also further amplified the ECL signal of luminol in the presence of hydrogen peroxide (H2O2). With the aid of Ag-rGO–Ab2–GOD, enhanced signal was obtained by in situ generation of H2O2 and catalysis of AgNPs to ECL reaction of the luminol–H2O2 system. The as-prepared ECL immunosensor exhibited excellent analytical property for the detection of CEA in the range from 0.1pgmL−1 to 160ngmL−1 with a detection limit of 0.03pgmL−1 (SN−1=3). •Hemin-GNs could further enhance the luminol ECL in the presence of H2O2.•Glucose oxidase was used to label the Ag-rGO–Ab2 for generating H2O2 in situ.•With the catalysis of AgNPs, amplified ECL signal could be obtained.•The immnuosensor exhibits high sensitivity, good stability and satisfying selectivity.