Experimental Techniques and MethodsElectrochemical Detection of Protein Based on Electroactive Nickel Hexacyanoferrate and Metallic Mimic Enzyme Synergistic Catalytic Enhancement
  
View Full Text    Download reader
DOI:
KeyWord:synergistic catalytic effect  electrochemical immunosensor  metallic nanoparticle  mimic enzyme
  
AuthorInstitution
ZHANG Li-na,XIE Xi-yue,CHAI Ya-qin 1.Jincheng Institute of Technology;2.College of Chemistry and Chemical Engineering,Southwest University
Hits: 1522
Download times: 662
Abstract:
      A ‘signal-off’ electrochemical immunosensor was designed for the ultra-sensitive detection of α-fetoprotein(AFP) based on the synergistic catalytic enhancement of metallic nano mimic enzyme to produce insoluble precipitation.The hollow gold-palladium-platinum nanoparticle bioconjugates(HAuNPs-PtPdNPs-Ab2) were immobilized on the electrode modified with electroactive substance nickel hexacyanoferrate nanoparticles through sandwich type immunoassay.In the presence of H2O2,HAuNPs and PtPdNPs as peroxidase-mimicking enzymes catalyzed 4-chloro-1-naphthol(4-CN) to generate insoluble and non-conductive precipitation benzo-4-chlorohexadienone(4-CD) at the electrode interface,thus effectively increasing the hindrance of electron transfer and leading to a significant decrease in electrochemical signal.The quantitative detection of AFP was achieved by the changes of electrochemical signal before and after the addition of AFP.Under the optimized reaction conditions,the experiment proved that the established immunosensor possessed a wider dynamic response from 0.1 pg/mL to 200 ng/mL in the detection of AFP with a low detection limit of 33 fg/mL.On the basis of the synergistic catalytic amplification,the proposed strategy could provide an effective method for multiple signal amplification to enormously improve the sensitivity of the biosensor.
Close