Construction of nanogold hollow balls with dendritic surface as immobilized affinity support for protein adsorption

This contribution introduced the construction of nano-size gold hollow balls (NGB) with dendritic surface as the immobilized affinity support for aflatoxin B1 antibody (anti-AFB1) adsorption, as a model protein, in biorecognition interface. The interaction between nanogold hollow balls and anti-AFB1 was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and quartz crystal microbalance (QCM) technique. The deposited mass of anti-AFB1 on the nanogold hollow ball-modified electrodes was more than that on the nanogold particle-modified electrodes via QCM analysis. The cyclic voltammogram tends to be more irreversible with anti-AFB1 concentration increased. The antigen–antibody interaction was examined by using the nanogold hollow ball-modified QCM probes. Experimental results show that the developed protein assay system is sensitive to the concentration of AFB1 as low as 0.05 ng mL−1. Thus, the nanogold hollow ball is a useful matrix, and can be used as the immobilized affinity support for the adsorption of other proteins.