The preparation of dual-functional hybrid nanoflower and its application in the ultrasensitive detection of disease-related biomarker.

In this work, dual-functional streptavidin (SA)-horseradish peroxidase (HRP) hybrid nanoflowers, integrating the functions of biological recognition and signal amplification, were prepared through facile one-pot green synthesis method. The prepared SA-HRP-Cu(PO) hybrid nanoflowers loaded abundant HRP and simultaneously exhibited enhanced catalytic activity, stability, and durability compared with free enzyme, which fits greatly well with the requirement of signal tag for bioassay. Besides, due to the general SA-biotin linking interaction, the SA-HRP-Cu(PO) hybrid nanoflowers possess universal capture ability to the biotinylated antibody. Hence, combined with enzyme-linked immunosorbent assay (ELISA), the dual-functional hybrid nanoflowers were used to construct a colorimetric sensor for the ultrasensitive detection of alpha-fetoprotein (AFP). The detection limit is 78pg/mL, which is far superior to commercial ELISA kits. This presented approach holds great promise to develop on-demand hybrid system for a variety of applications ranging from biosensor and biomedicine to biocatalytic process.