Genosensor for SARS Virus Detection Based on Gold Nanostructured Screen-Printed Carbon Electrodes

A hybridization-based genosensor is designed on a disposable gold nanostructured screen-printed carbon electrode. Gold nanoparticles which are formed in situ by applying a constant current intensity during a fixed time, acts as an immobilization and transduction surface. The parameters affecting the methodology are studied, with special attention being placed on sensibility. Immobilization takes place through thiol-gold interaction in a relatively fast way, and the genosensor response is found to be linearly to the biotinylated target concentration between 2.5 and 50 pmol/L; a detection limit of 2.5 pmol/L is calculated, and a sensitivity of 1.76 mu A/pmol L-1 is achieved. These results improve significantly those described in literature, thus demonstrating the advantages offered by the use of gold-nanostructured surfaces.