Facile fabrication of 2D MXene loading Co-doped Prussian blue nanoparticles for ultrasensitive electrochemical assay of trace lead ions

Lead ion (Pb 2+ ) is a significant environmental pollutant and severely harmed human health. Therefore, a direct and real-time detection for trace levels of Pb 2+ appear to be particularly important in environmental waters. In this work, we developed a portable electrochemical Pb 2+ sensor based on 2D MXene loading Co-doped Prussian blue, and CoPB-MXene/GCE exhibited a wide linear range of 1 to 200 nM and an ultralow detection limit of 0.97 nM under the low deposition potential of − 1.3 V (vs. Ag/AgCl). In addition, we investigated the various operating conditions, such as deposition time, buffer solution, and pH. Under the optimal conditions, the CoPB-MXene/GCE showed a high anti-interference, a good repeatability, an excellent reproducibility. Even more, CoPB-MXene/GCE still remains 89.23% of initial response current after four weeks, and exhibited an outstanding accuracy in real samples of bottle water, tap water, and lake water for Pb 2+ detection, which indicated the CoPB-MXene/GCE possessed an enormous potential for Pb 2+ detection in practical applications.