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We have fabricated potentially generalizable sensors based on polymeric-modified electrodes for the electrochemical detection of dopamine. Sensitive and selective sensors have been successfully obtained by applying a cold-plasma treatment during 1–2 min not only to conducting polymers but also to electrochemically inert polymers, such as polyethylene, polypropylene, polyvinylpyrrolidone, polycaprolactone and polystyrene. The effects of the plasma in the electrode surface activation, which is an essential requirement for the dopamine detection when inert polymers are used, have been investigated using X-ray photoelectron spectroscopy. Results indicate that exposure of polymer-modified electrodes to cold-plasma produces the formation of a large variety of reactive species adsorbed on the electrode surface, which catalyse the dopamine oxidation. With this technology, which is based on the application of a very simple physical functionalization, we have defined a paradox-based paradigm for the fabrication of electrochemical sensors by using inert and cheap plastics.

Polymeric sensors play an increasingly important role in monitoring the environment we live in, providing relevant information for a host of applications. Among them, significant efforts have been made to fabricate polymeric sensors useful for healthcare-related application fields, such as the sensitive detection of biomolecules and cellular interfacing. Within the well-established field of biomedical polymeric sensors, surface modification and/or functionalization using plasma is just emerging as a technology to improve selectivity and sensitivity in the biodetection process. Treatments based on plasma irradiation of polymer surfaces, which have been traditionally applied for cleaning, etching, activating or cross-linking, are currently being used to induce the formation of electrocatalytic species able to promote the oxidation of, for example, bioanalytes and/or gas molecules harmful for human health. Here, we summarize the main advances in the utilization of plasma technologies for the fabrication of polymeric sensors for advanced biomedical applications (e.g. humidity, temperature, pH, neurotransmitter, and glucose sensors).

"This is the peer reviewed version of the following article: Buendía JJ, Fabregat G, Castedo A, Llorca J, Alemán C. Plasma-treated polyethylene as electrochemical mediator for enzymatic glucose sensors: Toward bifunctional glucose and dopamine sensors. Plasma Process Polym. 2017;e1700133, which has been published in final form at https://doi.org/10.1002/ppap.201700133. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving The application of inert and insulating low density polyethylene (LDPE) in electrochemical detection is null. However, in a recent study it was found that reactive species formed onto the surface of plasma-treated LDPE and other polymers promote the electrocatalytic oxidation of dopamine. In this work, we examine the role of plasma-treated LDPE as mediator in enzymatic glucose biosensors based on Glucose oxidase and glass carbon substrate. Results indicate that plasma-induced changes facilitate the electrocommunication between the enzyme and the substrate. The chronoamperometric response of these sensors prove their bifunctionality since the oxidation of glucose to gluconolactone, which is catalyzed by the GOx, coexists with the oxidation of dopamine that is electrocatalytized by the plasma activated LDPE surface.

Amusement parks are excellent laboratories of physics, not only to check physical laws, but also to investigate if those physical laws might also be applied to human behaviour. A group of Physics Engineering students from Universitat Politecnica de Catalunya has investigated if human behaviour, when driving bumper cars, can be modelled using tools borrowed from the analysis of molecular dynamics simulations, such as the radial and angular distribution functions. After acquiring several clips and obtaining the coordinates of the cars, those magnitudes are computed and analysed. Additionally, an analogous hard disks system is simulated to compare its distribution functions to those obtained from the cars' coordinates. Despite the clear difference between bumper cars and a hard disk-like particle system, the obtained distribution functions are very similar. This suggests that there is no important effect of the individuals in the collective behaviour of the system in terms of structure. The research, performed by the students, has been undertaken in the frame of a motivational project designed to approach the scientific method for university students named FISIDABO. This project offers both the logistical and technical support to undertake the experiments designed by students at the amusement park of Barcelona TIBIDABO and accompanies them all along the scientific process.