No abstract

This paper concerns the development of an immunosensor for detection of Plum pox virus in plant extracts. The sensor was based on gold electrodes modified with: 1,6-hexanedithiol, gold nanoparticles, anti-PPV IgG polyclonal antibody and BSA. It was used for determination of the virus in extracts from plum (Prunus domestica) and tobacco (Nicotiana benthamiana) leaves. The proposed electrochemical impedance spectroscopy (EIS) immunosensor displayed a very good detection limit of 10 pg/mL and a wide dynamic range from 10 pg PPV/ mL to 200 pg/mL. The presence of extracts from plant materials has no influence on the immunosensors response. The immunosensor was capable of discriminating between samples from healthy plants and samples containing 0.01 % of extract from infected plant material. The conditions for immunosensor regeneration are also presented.

Immunosensors based on gold electrodes (electrochemical) or gold discs (optical) modified with 1,6-hexanedithiol, gold nanorods and Anti-His (C-term) monoclonal antibody F(ab’) fragment are described. The antigen detected by the sensing platform is a recombinant histidine-tagged silk proteinase inhibitor (rSPI2-His6). Electrochemical impedance spectroscopy (EIS) and surface plasmon resonance (SPR) techniques were used as methods for detection of the antigen. This approach allows to detect the antigen protein in concentration of 10 pg per mL (0.13 pM) of culture medium. The immunosensor shows good reproducibility due to covalent immobilization of F(ab’) fragments to gold nanorods layer.