Detection of avian influenza virus based on magnetic silica nanoparticles resonance light scattering system.

A highly sensitive method for the detection of avian influenza virus (AIV) antigen by the resonance light scattering (RLS) technique has been developed in this paper. Magnetic silica nanoparticles (MNs) were modified with AIV antibody via covalent binding firstly, the MNs/AIV antibody-AIV antigen immunocomplex was formed after the addition of AIV antigen, which can increase the RLS signal at 545 nm. Under the optimized conditions, the enhanced intensities of RLS at 545 nm (ΔI(RLS)) were proportional to the concentrations of AIV antigen in the range of 0.5-50 ng mL(-1), with a detection limit of 0.15 ng mL(-1) and correlation coefficient of 0.995. This method was applied to the analysis of AIV antigen in spiked chicken serum samples and saliva samples with satisfactory results.