Liana Devi D, Raguse Burkhard, Gooding J Justin, Chow Edith
CSIRO Manufacturing Flagship , P. O. Box 218, Lindfield, New South Wales 2070, Australia.
School of Chemistry, The University of New South Wales , Sydney, New South Wales 2052, Australia.
ACS Appl Mater Interfaces. 2015 Sep 2;7(34):19201-9. doi: 10.1021/acsami.5b04941. Epub 2015 Aug 19.
Paper-based sensors are gaining increasing attention for their potential applications in resource-limited settings and for point-of-care analysis. However, chemical analysis of paper-based electronic sensors is frequently interpreted using complex software and electronic displays which compromise the advantages of using paper. In this work, we present two semiquantitative paper-based readout systems that can visually measure a change in resistance of a resistive-based sensor. The readout systems use electrochromic Prussian blue/polyaniline as an electrochromic indicator on a resistive gold nanoparticle film that is fabricated on paper. When the readout system is integrated with a resistive sensor in an electrical circuit, and a voltage is applied, the voltage drop along the readout system varies depending on the sensor's resistance. Due to the voltage gradient formed along the gold nanoparticle film, the overlaying Prussian blue/polyaniline will change color at voltages greater than its reduction voltage (green/blue for oxidized state and transparent for reduced state). Thus, the changes in resistances of a sensor can be semiquantified through color visualization by either measuring the length of the transparent film (analog readout system) or by counting the number of transparent segments (digital readout system). The work presented herein can potentially serve as an alternative paper-based display system for resistive sensors in instances where cost and weight is a premium.
基于纸张的传感器因其在资源有限环境中的潜在应用以及即时护理分析而受到越来越多的关注。然而，基于纸张的电子传感器的化学分析常常需要使用复杂的软件和电子显示器来解读，这削弱了使用纸张的优势。在这项工作中，我们展示了两种半定量的基于纸张的读出系统，它们能够直观地测量基于电阻的传感器的电阻变化。这些读出系统在纸张上制备的电阻式金纳米颗粒薄膜上，使用电致变色普鲁士蓝/聚苯胺作为电致变色指示剂。当读出系统与电路中的电阻式传感器集成，并施加电压时，沿读出系统的电压降会根据传感器的电阻而变化。由于沿金纳米颗粒薄膜形成的电压梯度，覆盖的普鲁士蓝/聚苯胺在电压高于其还原电压时会变色（氧化态为绿色/蓝色，还原态为透明）。因此，传感器电阻的变化可以通过颜色可视化进行半定量，方法是测量透明薄膜的长度（模拟读出系统）或计算透明段的数量（数字读出系统）。在成本和重量至关重要的情况下，本文介绍的工作有可能作为电阻式传感器的一种替代的基于纸张的显示系统。
