ELECTROCHEMICAL DETECTION SYSTEM FOR THIOCHOLINE USING CLUSTER-ASSEMBLED ZIRCONIA MODIFIED GOLD ELECTRODES

In this work we report about a transducer based on gold electrodes modified with cluster-assembled zirconia nanostructured films produced by Supersonic Cluster Beam Deposition (SCBD) that can be implemented in a portable detection system for organophosphate compound pesticides based on electrochemical detection of Thiocholine. By using SCBD it is possible to quantitatively control the surface morphology, surface pores and surface specific area, as well as the roughness that depends on the film thickness. The nanoscale surface morphology and the nanopores have a substantial role in the processes involving the interaction of biological entities with nanostructured surfaces [1]. Here we show that cluster-assembled zirconia nanostructured films produced with SCBD are an effective promoter for electrochemical communication and it accelerates the transfer rate between the enzyme and the electrode. The atomic force microscopy assessment of the produced transducer has demonstrated that the nanostructured zirconia roughened the surface, therefore increasing the active surface area, and the electrochemical assessments (EIS and Chronoamperometry) of the produced electrodes have confirmed that by depositing the nanostructured zirconia thin films onto a conductive layer we are still able to maintain the electrochemical characteristics of the transducer and the detection of Thiocholine is possible. Also the compatibility of SCBD with planar fabrication techniques and additive manufacturing allows for the rapid and cheap fabrication of devices to be used in on-field portable detection systems. References: 1- Carsten Schulte, Alessandro Podestà, Cristina Lenardi, Gabriella Tedeschi and Paolo Milani- Quantitative control of protein and cell interaction with nanostructured surfaces by cluster assembling, Acc. Chem. Res., 2017, 50 (2), pp 231–239