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The electrical performance of screen‐printed dry electrodes on thermoplastic polyurethane substrates are evaluated according to their conformance to international standards, skin‐electrode impedance, and ability to gather high quality electrocardiograms. The electrical behavior of seven screen‐printed electrodes (Ag, Ag/PEDOT:PSS, Ag/AgCl, Ag/AgCl/PEDOT:PSS, C, C/AgCl, and PEDOT:PSS) is compared to two commercially available gel electrodes (3M RedDot 50 and Philips NeoLead) which represent the state‐of‐the‐art. After basic standard electrical characterization (electrode‐electrode impedance, DC offset voltage, defibrillation recovery, bias stress, and noise), it is shown that layers like AgCl or PEDOT:PSS help to reduce the contact impedance of dry electrodes. However, the quality of the electrical signal is primarily governed by the skin impedance, which, without physical disruption or preparation, maintains a high impedance. For this reason, the impedance of all screen‐printed dry electrodes allows the collection of electrocardiograms with a quality equal to that of gel electrodes. Dry electrodes, while capable of obtaining similar electrical signal quality also bring the advantages of reusability, comfort, and the capability for long‐term measurements.

In this paper we present the use of Photonic Crystals as chemical sensors. These 2D nanostructured sensors were prepared by nano-imprint lithography during which a nanostructure is transferred from a nickel template into a responsive polymer, that is be specifically tuned to interact with the chemical compound that must be detected. By creating a Photonic Crystal in a responsive polymer, the sensitivity of such a sensor can be greatly enhanced with respect to nanophotonic sensors that are only functionalized by a surface treatment. We have shown the functionality of an imprinted sensor by exposing the nanostructures to various liquids and vapours and monitor the change in reflected signal. Depending on the interactions and refractive index contrasts, the maximum wavelength of the reflected light can decrease (when exposed to toluene) or increase (when exposed to acetone). © 2011 Published by Elsevier Ltd.