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Microneedle‐based electrodes have attracted significant attention due to their potential applications in high‐quality, long‐term electrophysiological monitoring. In this study, micromoulding technology is used to develop a flexible, conductive fabric microneedle (CF–MN) electrode by bonding a conductive textile to polymeric microneedle arrays. The resulting electrode conforms to the curved surfaces of the body, and the use of a conductive textile backing reduces metallization time and costs by 50% over double‐sided dry electrodes. The electrode‐skin impedance of the CF–MN electrodes is significantly lower than that of gel electrodes over a wide frequency range, and tests on healthy volunteers, both at rest and under a range of ambulatory conditions, showed that the electrodes are capable of acquiring electrocardiography (ECG) and electromyography (EMG) signals that have a comparable kurtosis and signal‐to‐noise ratio to those recorded using conventional electrodes, but without the need for skin preparation or the use of a wet gel. The biomechanical properties of the electrode are also characterized. This is the first demonstration of CF–MN electrodes that can ultimately be integrated into clothing, which in turn can facilitate personalized cardiac health management by enabling continuous, long‐term ECG/EMG monitoring during daily activities. [ABSTRACT FROM AUTHOR]

Smart hydrogels for biomedical applications are highly researched materials. However, integrating them into a device for implantation is difficult. This paper investigates an integrated delivery device designed to deliver an electro-responsive hydrogel to a target location inside a blood vessel with the purpose of creating an occlusion. The paper describes the synthesis and characterization of a Pluronic/methacrylic acid sodium salt electro-responsive hydrogel. Application of an electrical bias decelerates the expansion of the hydrogel. An integrated delivery system was manufactured to deliver the hydrogel to the target location in the body. Ex vivo and in vivo experiments in the carotid artery of sheep were used to validate the concept. The hydrogel was able to completely occlude the blood vessel reducing the blood flow from 245 to 0 ml/min after implantation. Ex vivo experiments showed that the hydrogel was able to withstand physiological blood pressures of > 270 mm·Hg without dislodgement. The results showed that the electro-responsive hydrogel used in this paper can be used to create a long-term occlusion in a blood vessel without any apparent side effects. The delivery system developed is a promising device for the delivery of electro-responsive hydrogels. [ABSTRACT FROM PUBLISHER]

Abstract: This paper describes the electrochemical characterisation of a range of gold and platinum microelectrode arrays (MEAs) fabricated by standard photolithographic methods. The inter-electrode spacing, geometry, numbers and dimensions of the electrodes in the arrays were found to influence the voltammetric behaviours obtained. Excellent correlation was found between experimental data and theoretical predictions employing published models of microelectrode behaviour. Gold MEAs were evaluated for their applicability to copper determination in a soil extract sample, where agreement was found between the standard analytical method and a method based on underpotential deposition—anodic stripping voltammetry (UPD-ASV) at the MEAs, offering a mercury-free alternative for copper sensing. [Copyright &y& Elsevier]