LAUSR

In this work, a novel sandwich-type electrochemical immunosensor capable of detecting α-fetoprotein (AFP) was fabricated. In this process, the gold nanoparticles with unique biological and electrical properties were used as the substrate material for the immobilization of primary antibodies. Meanwhile, the as-obtained core-shell Pd@Pt nanoparticles-thionine composites with good biocompatibility and high indexed facets were selected as the label of signal antibodies towards hydrogen peroxide (H2O2) reduction to achieve signal amplification. Under the optimized conditions, the immunosensor for the detection of AFP exhibited a suitable linear response from 0.1 pg mL to 100 ng mL with a low detection limit of 0.035 pg mL (S/N = 3). Moreover, the immunosensor also showed acceptable stability, reproducibility and specificity, implying its potential application in bioassay analysis.