A self-assembled 3D nanoflowers based nano-ELISA platform for the sensitive detection of pyridaben

Biomimetic methods are invariably employed to synthesize hybrid organic-inorganic multilevel structure nanoflowers with self-assembly processes in aqueous solutions, which is an ideal way to meet the challenges of immobilizing antibodies or enzymes in nanomaterial based enzyme-linked immunosorbent assay (nano-ELISA). In this study, we developed protein-inorganic hybrid 3D nanoflowers composed of bovine serum albumin (BSA), horseradish peroxidase (HRP)-conjugated goat anti-mouse IgG (IgG-HRP) and copper(Ⅱ) phosphate (BSA-(IgG-HRP)-Cu₃(PO₄)₂) using a self-assembly biomimetic method. The preparation process avoided the use of any organic solvent and protein immobilization did not require covalent modifications. Additionally, the unique hierarchical structure enhances the thermal and storage stability of HRP. The BSA-(IgG-HRP)-Cu₃(PO₄)₂ hybrid 3D nanoflower was then applied to a nano-ELISA platform for pyridaben detection, achieving a 50% inhibition concentration of 3.90 ng mL^-1. The nano-ELISA achieved excellent accuracy for pyridaben detection. Such a novel BSA-(IgG-HRP)-Cu₃(PO₄)₂ hybrid 3D nanoflower provide an excellent reagent for small molecule immunoassay.