DETECTION OF NANO-STRUCTURED PARTICLES WITH ORGANIC ELECTRCHEMICAL TRANSISTORS

Recently big efforts have been addressed to the development of techniques for sensing and characterization of nanoparticles (NPs), especially in aqueous environment, due to their possible harmfulness related to their nanometric size. In this work we describe a real time detection of NPs based on organic electrochemical transistors (OECTs). OECTs were employed to detect core-shell super-paramagnetic NPs (Fe3O4) functionalized with different polymeric coatings. The OECT response resulted to be a function of the density of NPs suspended in the solution, with sensitivity down to tens of µg/ml. The data, interpreted in terms of the effective gate voltage shift induced by the NPs, indicate that the sensing mechanism is correlated to the electrostatic interaction of NPs with the PEDOT:PSS transistor channel.