Scaffold electrodes based on thioctic acid-capped gold nanoparticles coordinated Alcohol Dehydrogenase and Azure A films for high performance biosensor

Nanometric size gold nanoparticles capped with thiotic acid are used to coordinate with the Zn (II) present in the catalytic center of Alcohol Dehydrogenase (ADH). In combination with the NADH oxidation molecular catalyst Azure A, electrografted onto carbon screen-printed electrodes, they are used as scaffold electrodes for the construction of a very efficient ethanol biosensor. The final biosensing device exhibits a highly efficient ethanol oxidation with low overpotential of − 0.25 V besides a very good analytical performance with a detection limit of 0.14 ± 0.01 μM and a stable response for more than one month.This work has been supported by the Comunidad Autonoma de Madrid (NANOAVANSENS S2013/MIT 3029) and the Spanish Ministerio de Ciencia e Innovacion (project No. CTQ2011-28157).M. P. acknowledges the 2009 Ramon y Cajal program from the Spanish MINECO.Peer reviewe