Desenvolvimento de bioeletrodo para diagnóstico da toxoplasmose

Toxoplasma gondii is the intracellular protozoan parasite responsible for toxoplasmosis, a zoonosis with medical and veterinary importance worldwide [1]. The current work describe a system for the detection of specific target sequence for the toxoplasmosis diagnosis. The bioelectrode was developed on a graphite carbon electrode modified with poly (3-hydroxybenzoic acid) sensitized with specific oligonucleotide probe (TOXG1). Figures 1A and 1B show the differential pulse voltammogram and histogram of the bioelectrode current signal response (graphite/poly 3-HBA/TOXG1) in the absence and presence of the specific target (T. gondii genomic DNA) and a non-specific target (Neospora caninum genomic DNA). A decrease of about 20% in the guanosine signal response was observed due the extent of hybridization between the ToxG1 probe in the presence of T. gondii RH strain genomic DNA. This decrease is due to the formation of hydrogen bonds between the probe and complementary target during the hybridization, which hampers the oxidation of nitrogenous bases and indicate the hybridization in accordance with the literature [2]. The bioeletrode is selective, since the addition of the Neospora caninum genomic DNA not affect the current response and can be successfully applied in biological sample.