The air permeability of PDMS membranes is easily tuned acting on their composition. Varying the mixing ratio it is possible to strongly influence the gas molecules permeation across the PDMS membrane.

A label-free immunosensor based on an organic electrochemical transistor integrated with an immuno-affinity membrane for cytokine detection at physiologically relevant concentrations is reported.

Rapid Prototyping (RP) promises to induce a revolutionary impact on how the objects can be produced and used in industrial manufacturing as well as in everyday life. Over the time a standard technique as the 3D Stereolithography (SL) has become a fundamental technology for RP and Additive Manufacturing (AM), since it enables the fabrication of the 3D objects from a cost-effective photocurable resin. Efforts to obtain devices more complex than just a mere aesthetic simulacre, have been spent with uncertain results. The multidisciplinary nature of such manufacturing technique furtherly hinders the route to the fabrication of complex devices. A good knowledge of the bases of material science and engineering is required to deal with SL technological, characterization and testing aspects. In this framework, our study aims to reveal a new approach to obtain RP of complex devices, namely Organic Electro-Chemical Transistors (OECTs), by SL technique exploiting a resin composite based on the conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and the photo curable Poly(ethylene glycol) diacrylate (PEGDA). A comprehensive study is presented, starting from the optimization of composite resin and characterization of its electrochemical properties, up to the 3D OECTs printing and testing. Relevant performances in biosensing for dopamine (DA) detection using the 3D OECTs are reported and discussed too.

In this paper, a three-layer dielectric structure is presented as innovative unit-cell element for transmitarray (TA) antennas with enhanced bandwidth. It consists of a central layer, with a varying size square hole, used to compensate the phase of the incident field and located between two other identical layers with linearly tapered square holes, acting as matching circuits. The effectiveness of this unit-cell is demonstrated by the numerical and the experimental results here presented. As a first step, three different TAs with increasing size are designed and simulated: their 1-dB gain bandwidth, centered at 30 GHz, varies from the 30.9% of the smallest configuration, having size of 10λ ₀ x 10λ ₀ , to the 17.5% of the 20λ ₀ x20λ ₀ TA. A slightly modified unit-cell is then designed, with the aim of realizing a prototype with an additive manufacturing (AM) technique. A 3D-printed dielectric TA with a size of 15.6λ ₀ x15.6λ ₀ has been manufactured and experimentally characterized. The measured prototype shows excellent performances, achieving a 1-dB gain bandwidth of 21.5%: these results prove the enhanced features of the introduced unit-cell and demonstrate the TA feasibility with AM techniques.