Nitrogen and Sulfur Co-Doped Three-Dimensional Porous Carbon for Ultrasensitive Detection of Multiple Trace Heavy Metals in Food Samples

Due to the serious threat posed by heavy metal ions (HMIs) to food safety, a novel nitrogen and sulfur co-doped 3D porous carbon (NS-PC) material was synthesized for electrochemical detection. The optimized NS-PC modified electrode showed outstanding responses to Pb(II), Cu(II), and Hg(II). Individual detection limits were 1.1, 2.3, and 1.8 nM, respectively, while simultaneous detection limits were 2.6, 3.1, and 2.0 nM. Results for food samples matched ICP-MS data, validating the sensor’s accuracy and applicability. This provides an efficient HMI detection method, thereby expanding the application of electrochemical sensing in food safety.