A Paper-Based Electrochromic Array for Visualized Electrochemical Sensing

Fengling Zhang; Tianyi Cai; Liang Ma; Liyuan Zhan; Hong Liu

doi:10.3390/s17020276

A Paper-Based Electrochromic Array for Visualized Electrochemical Sensing

Sensors (Basel). 2017 Jan 31;17(2):276. doi: 10.3390/s17020276.

Authors

Fengling Zhang¹, Tianyi Cai², Liang Ma³, Liyuan Zhan⁴, Hong Liu^{5

6}

Affiliations

¹ State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. 220143702@seu.edu.cn.
² State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. 213143120@seu.edu.cn.
³ State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. 213140698@seu.edu.cn.
⁴ State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. 213143432@seu.edu.cn.
⁵ State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. liuh@seu.edu.cn.
⁶ Laboratory of Environment and Biosafety, Research Institute of Southeast University in Suzhou, Suzhou 215123, China. liuh@seu.edu.cn.

Abstract

We report a battery-powered, paper-based electrochromic array for visualized electrochemical sensing. The paper-based sensing system consists of six parallel electrochemical cells, which are powered by an aluminum-air battery. Each single electrochemical cell uses a Prussian Blue spot electrodeposited on an indium-doped tin oxide thin film as the electrochromic indicator. Each electrochemical cell is preloaded with increasing amounts of analyte. The sample activates the battery for the sensing. Both the preloaded analyte and the analyte in the sample initiate the color change of Prussian Blue to Prussian White. With a reaction time of 60 s, the number of electrochemical cells with complete color changes is correlated to the concentration of analyte in the sample. As a proof-of-concept analyte, lactic acid was detected semi-quantitatively using the naked eye.

Keywords: POCT; battery; electrochromism; paper.