Paper-Based Sensor Chip for Heavy Metal Ion Detection by SWSV

Abstract

Heavy metal ion pollution problems have had a terrible influence on human health and the environment. Therefore, the monitoring of heavy metal ions is of great practical significance. In this paper, an electrochemical three-electrode system was fabricated and integrated on nitrocellulose membrane (NC) by the use of magnetron sputtering technology, which exhibited a uniform arrangement of porous structure without further film modification. This paper-based sensor chip was used for Cu ²⁺ detection by square-wave stripping voltammetry (SWSV). Within the ranges of 5–200 μg·L ⁻¹ and 200–1000 μg·L ⁻¹, it showed good linearity of 99.58% and 98.87%, respectively. The limit of detection was 2 μg·L ⁻¹. On the basis of satisfying the detection requirements (10 μg·L ⁻¹), the integrated sensor was small in size and inexpensive in cost. Zn ²⁺, Cd ²⁺, Pb ²⁺ and Bi ³⁺ were also detected by this paper-based sensor chip with good linearity.