A flexible electrochemical sensor based on AuBi bimetal for detection of Cd ions in packaged drinking water

• An AuBi bimetal film is modified onto a flexible screen-printed electrode by electrodeposition. • A flexible electrochemical Cd sensor is demonstrated successfully based on AuBi bimetal modified flexible screen-printed electrode. • The developed sensor successfully achieves a high sensitivity, a low detection limit and a wide linear range to Cd ions detection. • The developed sensor verifies acceptable accuracy and precision for Cd ions detection in practical packaged drinking water. Heavy metal ion Cd, as a toxic pollutant, can accumulate in human body through the bioaccumulation effect of food chain and poses a threat to human health. Packaged drinking water is one of the main water sources for many people, making it crucial to detect their cadmium ion levels. In this work, an AuBi bimetal film was electrodeposited onto a flexible screen-printed electrode to construct highly sensitive cadmium ion sensors. The prepared sensor could enrich trace cadmium ions in the target electrolyte, followed by sensitive detection of cadmium ions using stripping wave voltammetry. The electrochemical results demonstrated that the developed sensor based on AuBi bimetal exhibited a significant linear response to cadmium ions in the range of 50 μg/L to 800 μg/L, with a low detection limit of 11.68 μg/L (S/N=3), and it also showed good repeatability. The prepared flexible electrochemical sensor was employed to detect the cadmium ion level in five common types of packaged drinking water available on the market, and the relative standard deviation (RSD) and recovery were within normal ranges, indicating that it could achieve rapid and sensitive detection of cadmium ion level in drinking water and other foodstuffs. A flexible electrochemical sensor based on AuBi bimetal is developed for the detection of cadmium ions. By sequentially modifying the screen-printed carbon electrode with gold and bismuth using by electrodeposition, a highly sensitive cadmium ion sensor is constructed. The prepared sensor could enrich trace cadmium ions in the target electrolyte, followed by sensitive detection of cadmium ions using stripping wave voltammetry. The electrochemical results demonstrated that the developed sensor based on AuBi bimetal exhibited an excellent linear response and good repeatability. The test results obtained from actual samples indicates that it could achieve rapid and sensitive detection of cadmium ion level in packaged drinking water.