Electrochemical Sensor for Cd2+ Detection Based on Carbon Fiber Paper Sequentially Modified With CoMOF, AuNPs, and Glutathione.

Cadmium ion (Cd2+) is one of the toxic heavy metals in the environment. Even small amounts of Cd2+ may cause environmental pollution and threaten human life and health. Here, an electrochemical sensor for Cd2+ detection was established using a complex of carbon fiber paper (CFP), CoMOF, AuNPs, and glutathione as the conductive substrate (CFP/CoMOF/AuNPs/GSH). Compared with traditional methods for heavy metals detection, electrochemistry owns the advantages of high sensitivity, easy miniaturization, and portability. In addition, general conductive substrate is replaced by a new nanomaterial, CFP/CoMOF/AuNPs/GSH, which improves the performance greatly. In the presence of Cd2+, GSH is chelated to Cd2+, resulting in a redox peak appearing around -0.84 V. Thus, a sensitive and easily portable electrochemical sensor for Cd2+ detection has been developed. Under optimal conditions, the established electrochemical sensor achieves Cd2+ detection low to 1 nM. Selectivity and reproducibility experiments show that the sensor has good analytical performance. This provides a direction for the use of electrochemistry to detect heavy metal ions. [ABSTRACT FROM AUTHOR]