Cell Viability Assessment of PEDOT Conducting Polymer-Coated Microneedles for Skin Sampling.

Recently, transdermal monitoring and drug delivery have gained much interest, owing to the introduction of the minimally invasive microneedle (MN) device. The advancement of electroactive MNs electrically assisted in the capture of biomarkers or the triggering of drug release. Recent works have combined conducting polymers (CPs) onto MNs owing to the soft nature of the polymers and their tunable ionic and electronic conductivity.

PEDOT coated microneedles towards electrochemically assisted skin sampling.

Skin sampling is a diagnostic procedure based on the analysis of extracted skin tissues and/or the observation of biomarkers in bodily fluids. Sampling using microneedles (MNs) that minimize invasiveness is gaining attention over conventional biopsy/blood lancet. In this study, new MNs for electrochemically assisted skin sampling are reported, specifically tailored for combined skin tissue biopsy and interstitial fluid (ISF) extraction.

Understanding PEDOT doped with tosylate.

Now in their 5th decade of research and development, conducting polymers represent an interesting class of materials to underpin new wearable or conformable electronic devices. Of particular interest over the years has been poly(3,4-ethylenedioxythiophene), commonly known as PEDOT, owing to its ease of fabrication and relative stability under typical ambient conditions. Understanding PEDOT from a variety of fundamental and applied perspectives is important for how it can be enhanced, modified, functionalised, and/or processed for use in commercial products.

Influence of Postsynthesis Heat Treatment on Vapor-Phase-Polymerized Conductive Polymers.

The effect of thermal treatment on the structure and electrical/optical properties of vapor phase-polymerized poly(3,4-ethylenedioxythiophene):tosylate (PEDOT:Tos) and polypyrrole:tosylate (PPy:Tos) polymer films was investigated. Thermal treatment was applied postpolymerization but prior to washing the embedded oxidant layer out of the polymer film. Structural and chemical changes arising from the treatment were studied in the context of their conductive and electrochromic behavior.

Acido-basic control of the thermoelectric properties of poly(3,4-ethylenedioxythiophene)tosylate (PEDOT-Tos) thin films.

PEDOT-Tos is one of the conducting polymers that displays the most promising thermoelectric properties. Until now, it has been utterly difficult to control all the synthesis parameters and the morphology governing the thermoelectric properties. To improve our understanding of this material, we study the variation in the thermoelectric properties by a simple acido-basic treatment.

Laser actuation of cantilevers for picometre amplitude dynamic force microscopy.

As nanoscale and molecular devices become reality, the ability to probe materials on these scales is increasing in importance. To address this, we have developed a dynamic force microscopy technique where the flexure of the microcantilever is excited using an intensity modulated laser beam to achieve modulation on the picoscale. The flexure arises from thermally induced bending through differential expansion and the conservation of momentum when the photons are reflected and absorbed by the cantilever.

Aqueous processing of graphene-polymer hybrid thin film nano-composites and gels.

Research into the structure, properties and applications of graphene has moved at a tremendous pace over the past few years. This review describes one aspect of this research, that of the incorporation of graphene particles with a range of polymers to create novel hybrid materials with increased functionality such as improved conductance, increased strength and introduced biocompatibility or cytotoxicity. This review focuses on dispersing graphene in polymer matrices, both insulating and conducting.

Semi-metallic polymers.

Polymers are lightweight, flexible, solution-processable materials that are promising for low-cost printed electronics as well as for mass-produced and large-area applications. Previous studies demonstrated that they can possess insulating, semiconducting or metallic properties; here we report that polymers can also be semi-metallic. Semi-metals, exemplified by bismuth, graphite and telluride alloys, have no energy bandgap and a very low density of states at the Fermi level.

Physical properties of phase-change emulsions.

Phase-change emulsions (PCE) are important in a variety of applications, from ultrasound imaging to the explosive material used in the mining industry, but until now there has been no adequate theory to describe their activation properties. The PCE consists of a low-boiling-point liquid, known as the volatile phase, dispersed in an aqueous phase. The volatile phase boils as a result of an increase in the temperature of the emulsion.

The origin of surface stress induced by adsorption of iodine on gold.

The cantilever technique for the measurement of film stress on both macroscopic and microscopic cantilevers is validated, then applied to the experimental determination of film stress induced by the adsorption of a monolayer of iodine onto a gold substrate. A model is proposed that relates the change in the interatom potential upon chemisorption of iodine onto gold to the measured film stress. Excellent agreement is found with the experimentally determined value.

Sensing cantilever beam bending by the optical lever technique and its application to surface stress.

Cantilever beams, both microscopic and macroscopic, are used as sensors in a great variety of applications. An optical lever system is commonly employed to determine the deflection and thereby the profile of the cantilever under load. The sensitivity of the optical lever must be calibrated, and this is usually achieved by application of a known load or deflection to the free end of the cantilever.