Gradient-Based Colorimetric Array Sensor for Continuous Monitoring of Multiple Gas Analytes

• DOI: 10.1021/acssensors.0c01971
• Publication Date: 2020-12-18T12:29:29Z
• Authors: Chenwen Lin; Zijian Du; Nongjian Tao; Di Wang
• Keywords: Colorimetry; Sensor array

Colorimetry is widely used in chemical sensing due to its high sensitivity and selectivity. However, most colorimetric sensors are one-time use because the color-producing reactions or bindings usually irreversible. In addition, traditional like detection tubes bulky packed individually, making parallel of multiple analytes difficult. Here, we demonstrate a gradient-based array sensor (GCAS) overcome these limitations. Different elements inkjet-printed as straight lines on porous substrate. Lateral transport across substrate creates color gradients elements. The shift along direction over time, GCAS tracks gradient shifts converts them into analyte concentrations real time. Using low-cost complementary metal-oxide semiconductor imager, show three air pollutants using single chip 24 h continuous monitoring ambient ozone.