Department of Chemistry , Colorado State University , Fort Collins , Colorado 80523 , United States.
Department of Pharmaceutical Chemistry, School of Pharmacy , Universitas Gadjah Mada , Yogyakarta , Indonesia.
Anal Chem. 2019 Feb 5;91(3):2431-2438. doi: 10.1021/acs.analchem.8b05218. Epub 2019 Jan 24.
Electrochemical paper-based analytical devices (ePADs) have garnered significant interest as an alternative to traditional benchtop methods due to their low cost and simple fabrication. Historically, ePADs have relied almost exclusively on single electrode detection, limiting potential gains in sensitivity and selectivity achievable with multiple electrodes. Herein we describe incorporation of thermoplastic electrode (TPE) arrays into flow ePADs. Quasi-steady flow was solely generated by capillary action through a fan-shaped paper device. The electrode arrays were fabricated using a simple solvent-assisted method with inexpensive materials (i.e., graphite and thermoplastic binder). These electrodes can be employed as an array of individually addressable detectors or connected as an interdigitated electrode array. The TPEs were characterized through SEM, optical profilometry and cyclic voltammetry. Chronoamperometry was used to characterize the flow-based TPE-ePADs. Trace detection of a ferrocene complex (FcTMA) was demonstrated through generation-collection experiments, achieving a limit of detection of 0.32 pmol. These TPE arrays containing ePADs show great promise as a rapid, sensitive, and low-cost sensor for point-of-need (PON) applications.
电化学纸质分析器件（ePAD）由于其低成本和简单的制造工艺，已经引起了人们的极大兴趣，可以作为传统台式方法的替代品。历史上，ePAD 几乎完全依赖于单电极检测，限制了通过多电极实现的灵敏度和选择性的潜在提高。在此，我们描述了将热塑性电极（TPE）阵列纳入流动 ePAD 中。准稳态流动仅通过扇形纸质器件中的毛细作用产生。电极阵列是使用简单的溶剂辅助方法和廉价材料（即石墨和热塑性粘合剂）制造的。这些电极可以用作单独寻址的检测器阵列，也可以连接成叉指电极阵列。通过 SEM、光学轮廓术和循环伏安法对 TPE 进行了表征。通过生成-收集实验对基于时间的 TPE-ePAD 进行了chronoamperometry 表征。通过生成-收集实验，通过生成-收集实验证明了对二茂铁配合物（FcTMA）的痕量检测，检测限达到 0.32 pmol。这些包含 ePAD 的 TPE 阵列有望成为用于即时（PON）应用的快速、灵敏和低成本传感器。
