A highly sensitive electrochemical immunosensor based on coral-shaped AuNPs with CHITs inorganic–organic hybrid film

A highly sensitive electrochemical immunosensor based on combination of chitosan (CHIT) and coral-shaped AuNPs (C-AuNPs) to form an immobilization matrix has been developed using human IgG as a model analyte. The inorganic–organic hybrid film with abundant adsorbing sites and large surface area can reserve the biocompatibility of the biomaterials which greatly increase loading amounts of assembling, thus, significantly improves the performance of biosensing. The morphology is studied by scanning electron microscopy (SEM). Under the optimized experimental conditions, the immunosensor exhibits excellent performance (e.g., a detection limit of 5 pmol L−1, a linear dynamic range of 3 orders of magnitude, high specificity). This possibly makes it an attractive platform for the direct immunoassay of human IgG or other biomolecules.