Ring like self assembled Ni nanoparticles based biosensor for food toxin detection

The self-assembled ring like nickel (RnNi∼10-20nm) nanoparticles have been prepared by pulsed laser ablation method and confirmed by transmission electron microscopy. These RnNi nanoparticles electrophoretically deposited onto the indium-tin-oxide (ITO) glass substrate have been functionalized with dimethyl sulfoxide (DMSO) for covalent immobilization of anti-aflatoxin (a-AfB1) monoclonal antibodies and bovine serum albumin as blocking agent. The electrochemical response studies of a-AfB1/DMSO/RnNi-film/ITO bioelectrode reveal linearity as 5-100ngdL −1 , detection limit of 32.7ngdL −1 , sensitivity of 0.59 μ A/ngdL −1 , and shelf-life of 60days. The low value (1.3×10 14 molL −1 ) of association constant ( K a ) shows high affinity towards aflatoxin.