The design of optical nanobiosensor as a novel method for diagnosis of Toxoplasma gondii infection

Abstract

Background: Toxoplasma gondii is an intracellular protozoan parasite and a cause of toxoplasmosis with widespread worldwide distribution. Serologic methods such as ELISA, Dye test, indirect hemagglutination and latex agglutination are used to diagnose toxoplasmosis. But these methods require specialized equipment and equipment and are time consuming and costly. Materials and Methods: To design an optical nano-biosensor system to detect Toxoplasma gondii infection, first, gold nanoparticles were synthesized using chitosan as a reducing and stabilizing agent. Chitosan-gold nanoparticles were then activated with glutaraldehyde and conjugated with anti-IgG and anti-IgM antibodies. Subsequently, Toxoplasma Lysate Antigen (TLA) was coated on nitrocellulose membrane and after placing the membrane in the serum sample, the samples were embedded in gold-chitosan-antibody conjugated solutions. Results: In the designed system, the conjugated nanoparticles to the antibodies as a green probe were able to detect anti-Toxoplsma IgG and anti-Toxoplasma IgM in serum sample.