All-in-Fiber Electrochemical Sensing

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.

Thermally drawn multifunctional fibers: Toward the next generation of information technology

“…The built‐in electrode makes the fiber a promising candidate for electrochemical analysis. More importantly, integrating photodetection devices inside the fiber eliminates the need for external detectors and provides the potential for distributed chemical sensing 98 …”

“…Richard et al proposed the first fiber integrated electrochemical devices by tailoring the fiber microstructure 98 . The fiber configuration is depicted in Figure 6A,B.…”

“…(A,B) Schematic and optical micrograph of the hollow core fiber cross‐section, respectively. Reproduced with permission 98 . Copyright 2021, American Chemical Society.…”

“…(C) Cyclic voltammograms for paracetamol concentrations between 10 and 300 μM. Reproduced with permission 98 . Copyright 2021, American Chemical Society.…”

“…(D) Schematic of the hollow core electrochemical fiber attached to a pipet tip via heat‐shrink tubing. Reproduced with permission 98 . Copyright 2021, American Chemical Society.…”