Nano-Sized Elements in Electrochemical Biosensors

Abstract

The emerging nanotechnology has opened novel opportunities to explore analytical applications of the fabricated nano-sized materials. Recent advances in nano-biotechnology have made it possible to realize a variety of enzyme electrodes suitable for sensing application. In coating miniaturized electrodes with biocatalysts, undoubtedly the most of the potential deposition processes suffer from the difficulty in depositing process and reproducible coatings of the active enzyme on the miniature transducer element. The promising prospects can concern to the obtaining of thin protein layers by using, i.e . electrochemical deposition, electrophoretic deposition as well as monolayer methods (Langmuir-Blodgett procedure, Layer-by-Layer — LbL). Many aspects dealing with deposition of enzyme by techniques employing electric field are considered, including surface charge of enzyme, and its migration under applied electric filed. The using of nanoscale materials ( i.e . nanoparticles, nanowires, nanorods) for electrochemical biosensing has seen also explosive increase in recent years following the discovery of nanotubes. These structures offer a promise in the development of biosensing, facilitating the great improvement of the selectivity and sensitivity of the current methods. Finally, the perspectives in the further exploration of nanoscaled sensors are discussed.