Ultrasensitive sensor based on novel bismuth carbon nanomaterial for lead and cadmium determination in natural water, contaminated soil and human plasma

Abstract Heavy metals are ubiquitous in the environment, and their excessive discharge and bioaccumulation can cause cardio-vascular and urinary diseases in humans. Among them, lead ion (Pb2+) and cadmium ions (Cd2+) are designated as the most typical toxic metal ions in human blood and drinking water. Thus, high-performance monitoring of Pb2+and Cd2+ pollution is necessary. Nanomaterials have been extensively used in electrochemical sensing due to their excellent physicochemical properties. In this study, we prepared ordered mesoporous carbon doped hollow spherical bismuth oxide nanocomposites (hsBi2O3-OMC NCs), and constructed it into an electrochemical sensor for highly sensitive and specific detection of Pb2+ and Cd2+ in environmental media and human blood based on the differential pulse anodic stripping voltammetry (DPASV). The experimental results demonstrate that the detection range could be broadened to 200 nM with detection limits of 0.025 nM for Pb2+ and 0.045 nM for Cd2+. Compared with conventional detection techniques, this sensor exhibited simple operation, minimal background interference, multipath applicability and economic efficiency. Therefore, we believe that this work is significant for pollution monitoring, environmental restoration and emergency treatment.