The preparation of hollow AgPt@Pt core-shell nanoparticles loaded on polypyrrole nanosheet modified electrode and its application in immunosensor

Abstract

The designed synthesis of efficient materials can significantly enhance the performance of electrochemical immunoassay in the detection of diseases, pesticide residues and environmental pollutants. The hollow AgPt@Pt core-shell nanoparticles (AgPt@Pt HNs) have exhibited high catalytic efficiency to the hydrogen peroxide (H2O2) reduction for its high mass activity from their hollow structure. Their limitation of instability can be overcome by loading on polypyrrole nanosheet (PPy NS). Besides, PPy NS exhibits good conductivity, and there exists environmentally-friendly method for its synthetic. Thus, AgPt@Pt HNs loaded on PPy NS (AgPt@Pt HNs/PPy NS) exhibits high catalytic efficiency to the reduction of H2O2 and good stability. Furthermore, the quick electron transfer of AgPt@Pt HNs/PPy NS modified glassy carbon electrode has been evidenced by the finding that the large constant of apparent electron transfer rate has also enlarged the current signal when the amount of electron is invariant. The modified electrode has fabricated a label-free amperometric immunosensor to detect sensitively prostate-specific antigen (PSA) with H2O2 as the electroactive material. The immunosensor in hollow core-shell nanosheet structure exhibiting good detection performance of PSA shows its promising applications in the clinical diagnosis.