A dual amplification strategy for ultrasensitive electrochemiluminescence immunoassay based on a Pt nanoparticles dotted graphene-carbon nanotubes composite and carbon dots functionalized mesoporous Pt/Fe

• Published in: Analyst (London) 2014-04, Vol.139 (7), p.1713-172
• Main Authors: Deng, Wenping, Liu, Fang, Ge, Shenguang, Yu, Jinghua, Yan, Mei, Song, Xianrang
• Format: Article
• Language: English
• Subjects: Alloys; Amplification; Biosensing Techniques; Carbon; Carcinoembryonic Antigen - analysis; Electrochemical Techniques - instrumentation; Electrochemical Techniques - methods; Electrochemiluminescence; Graphite - chemistry; Humans; Immunoassay - instrumentation; Immunoassay - methods; Immunosensors; Iron; Iron - chemistry; Luminescent Measurements - instrumentation; Luminescent Measurements - methods; Metal Nanoparticles - chemistry; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Nanoparticles; Nanotubes; Nanotubes, Carbon - chemistry; Platinum; Platinum - chemistry; Porosity; Quantum Dots - chemistry; Surface Properties
• ISSN: 0003-2654; 1364-5528
• DOI: 10.1039/c3an02084c

A facile and sensitive electrochemiluminescence (ECL) immunosensor for the detection of human carcinoembryonic antigen (CEA) was designed. The immunosensor used Pt nanoparticles dotted graphene-carbon nanotubes composites (Pt/Gr-CNTs) as a platform and carbon dots functionalized Pt/Fe nanoparticles (Pt/Fe@CDs) as bionanolabels. The Pt/Gr-CNTs was first synthesized using a facile ultrasonic method to modify the working electrode, which increases the surface area to capture a large amount of primary anti-CEA antibodies as well as improving the electronic transmission rate. The bionanolabels Pt/Fe@CDs prepared through ethanediamine linking, showed good ECL signal amplification performance. The reason is that the Pt/Fe@CDs nanocomposites as signal tags can increase CDs loading per immunoreaction in comparison with single CDs. The approach provided a good linear response range from 0.003 to 600 ng mL −1 with a low detection limit of 0.8 pg mL −1 . The immunosensor showed good specificity, acceptable stability and reproducibility. Satisfactory results were obtained in the determination of CEA in human serum albumin samples. Hence, the proposed ECL immunosensor could become a promising method for tumor marker detection. A facile and sensitive ECL immunosensor has been designed using Pt/Gr-CNTs as a platform and Pt/Fe@CDs as bionanolabels.