Ni(OH)2/NGQDs-based electrochemiluminescence immunosensor for prostate specific antigen detection by coupling resonance energy transfer with Fe3O4@MnO2 composites

Biosens Bioelectron. 2018 Jan 15:99:346-352. doi: 10.1016/j.bios.2017.08.005. Epub 2017 Aug 4.

Abstract

An efficient quenching electrochemiluminescence (ECL) immunosensor based on ECL resonance energy transfer (ECL-RET) was studied for sensitive analysis of prostate specific antigen (PSA). In this protocol, nitrogen-doped graphene quantum dots (NGQDs) which could produce excellent ECL emission, were loaded onto Ni(OH)2 with the three-dimensional (3D) hierarchical and stacked lamellar structure. Taking advantages of high conductivity and large specific surface area of Ni(OH)2, the better electrochemical and ECL behavior of Ni(OH)2/NGQDs were presented. As another part of immunosensor, the Fe3O4@MnO2 composites with wider ultraviolet absorption range were successfully assembled. The absorption spectra of Fe3O4@MnO2 precisely overlapped with the ECL spectra of NGQDs, leading to the significant decrement of ECL signal. Herein, the sandwich-type immunosensor was developed based on the quenching mechanism between NGQDs (ECL donor) and Fe3O4@MnO2 (ECL acceptor). The system was optimized to realize reliable determination of PSA concentration within the linear range of 10-5-10ng/mL and a detection limit of 5 fg/mL (S/N = 3). Eminently, the developed method was successfully applied in real serum samples with good recoveries in a range from 94.0% to 102%, indicating the good accuracy of the proposed method for PSA detection.

Keywords: Electrochemiluminescence; Nitrogen doped graphene quantum dots; Prostate specific antigen; Resonance energy transfer.

MeSH terms

  • Biosensing Techniques*
  • Electrochemical Techniques*
  • Fluorescence Resonance Energy Transfer
  • Gold / chemistry
  • Graphite / chemistry
  • Humans
  • Limit of Detection
  • Luminescent Measurements
  • Metal Nanoparticles / chemistry*
  • Nitrogen / chemistry
  • Prostate-Specific Antigen / chemistry
  • Prostate-Specific Antigen / isolation & purification*
  • Quantum Dots / chemistry

Substances

  • Gold
  • Graphite
  • Prostate-Specific Antigen
  • Nitrogen