Electro-nano diagnostic platforms based on neuraminidase and hemagglutin: development of model systems for diagnosis of influenza and cancer

In this doctoral thesis, neuraminidase (NEU3) and hemaglutinin (H) based electrochemical model diagnosis systems were developed for cancer cells and Influenza A virus. Present work consist of two sections. In the first section, the development of NEU3 based model cancer electrochemical biosensor is described. For this purpose, first gold screen printed electrode (AuSPE) was modified with Grafen-Platinum hybrid nanoparticle. Then the sialic acid (SA) source GD3 ganglioside, which interacts specifically with a cancer biomarker NEU3, was immobilized on to the electrode surface. Indirect determination of NEU3 was carried out through the the specific binding of PNA Lectin to galactose units released when NEU3 enzyme in the medium cleaveges the GD3 ganglioside on the electrode surface from the SA ends. Sample application study of the developed model system was carried out with HeLa cancer cell lines. All electrochemical measurements were performed using the electrochemical impedance spectroscopy (EIS) method. In the second section, H1N1 and H3N2 inactive viruses were used as models to develop two different anti-H based electrochemical model immunosensors for the diagnosis of Influenza A. In order to detect H1N1 inactivated virus, anti-H1 antibodies were immobilized on multi-walled carbon nanotube-gold-platinum hybrid nanoparticle modified AuSPE surface. On the other hand, anti-H3 antibodies were immobilized on Graphene-Gold hybrid nanoparticle modified AuSPE surface to detect H3N2 inactive virus. Both Influenza model immunosensors were tested using H1N1 and H3N2 inactive viruses. The specific interactions between anti-H1 antibody and H1N1 and also between anti-H3 antibody and H3N2 were examined by EIS. The serum matrix effect was also investigated using a synthetic saliva supplemented with the standard H1N1 and H3N2 viruses.