No abstract

Electrochemical sensors have found a wide range of applications in analytical chemistry thanks to the advent of high-throughput printing technologies. However, these techniques are usually limited to two-dimensional (2D) geometry with relatively large minimal feature sizes. Here, we report on the scalable fabrication of monolithically integrated electrochemical devices with novel and customizable fiber-based architectures. The multimaterial thermal drawing technique is employed to co-process polymer composites and metallic glass into uniform electroactive and pseudoreference electrodes embedded in an insulating polymer cladding fiber. To demonstrate the versatility of the process, we tailor the fiber microstructure to two configurations: a small-footprint fiber tip sensor and a high-surface-area capillary cell. We demonstrate the performance of our devices using cyclic voltammetry and chronoamperometry for the direct detection and quantification of paracetamol, a common anesthetic drug. Finally, we showcase a fully portable pipet-based analyzer using low-power electronics and an “electrochemical pipet tip” for direct sampling and analysis of microliter-range volumes. Our approach paves the way toward novel materials and architectures for efficient electrochemical sensing to be deployed in existing and novel personal care and surgical configurations.

Monitoring of patient response to the anaesthetic drugs is an attractive improvement for achieving a correct balance of sedation level, increasing the chance of success in the right procedure of anaesthesia. Nowadays, there are no commercial tools able to offer real-time monitoring of anaesthetics, indeed, there is still a lack in sensing technologies able to maintain high performances in long term monitoring within a portable miniaturised hardware system. To overcome these limitations, we are here presenting the innovative concept of a portable pen-device able to sense anaesthetic compounds over time. This study is based on an electrochemical sensor to be fully integrated into a complete pen-shaped point-of-care for the monitoring of anaesthesia delivery. The design of the system is based on a bio-inspired event-based approach that is guaranteeing low complexity, low power consumption and is therefore suitable to be scaled to fit the barrel of a pen. An exhaustive comparison between the proposed system and a lab instrument proves that the presented approach obtains comparable performances in terms of sensitivity and resolution with the ones obtained by expensive commercial instrumentation, meanwhile, the results show a 95 % power consumption reduction and a 92 % area decrease w.r.t. previously presented implementation. Index Terms-Anaesthesia, bio-inspired, biosensor, portable, quasi digital, therapeutic drug monitoring.

The recent advancements in electrochemical measurements are guiding the development of new platforms for in-situ point-of-care monitoring of human-metabolite, markers and drugs. Despite this, the application of Voltammetry-Based Sensing (VBS) techniques is still limited in wearable, portable, or IoT systems. In order to use VBS approaches to measure analytes in small and low-power electronic platforms for diagnostics, several improvements are required. For example, the definition of a method to achieve the right trade-off between sample rate and sensing performance is still missing. To develop a method to define the best sampling rate, we present here an extensive analysis of experimental data to prove that is feasible to detect drugs such as paracetamol by Staircase Cyclic Voltammetry (SCV) or Differential Pulse Voltammetry (DVP) direct detection methods, with low sampling frequency. Our results prove that the proposed method helps the development of systems capable of discriminating the minimum pharmacology concentration of the metabolite under analysis with a massive reduction of the sampling frequency.