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

The self-assembled ring like nickel (RnNi similar to 10-20 nm) 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 5-100 ng dL(-1), detection limit of 32.7 ngdL(-1), sensitivity of 0.59 mu A/ng dL(-1), and shelf-life of 60 days. The low value (1.3 x 10(14) molL(-1)) of association constant (K-a) shows high affinity towards aflatoxin. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3690044]