A novel electrochemical sensor for the ultrasensitive monitoring of Pb²⁺ and Cd²⁺ was developed by fabrication of highly conductive and target selective electrode using ball milling biochar (BBC) featured with high conductivity and rich oxygenic functional groups as the conductive material, and cavities of ion-imprinted polymer as specific binding moieties. The nanosized BBC was synthesized with process of high temperature pyrolysis and rigorous ball milling. The ion imprinted BBC electrode was constructed by in situ electropolymerization of L-Cysteine and template metal ions on the BBC that was modified on glassy carbon, and subsequent removal of templates. The BBC presented great electron transfer ability, and contained increased oxygenic compounds than the mild ball milling prepared one, which attributed to formation of stable and cavity-rich imprinting polymer layer and enhancement of sensing signal. With the anodic dissolved differential pulse voltammetry, the electrode could detect extremely low levels of Pb²⁺ and Cd²⁺ with lowest detection limits of 5.86 fM and 0.883 aM, and the linear ranges were 25 fM ~ 1 µM and 0.1 fM ~ 1 µM, respectively. The electrode also presented anti-interference to other irrelevant ions and organic compounds, and could reuse at least seven times without decrease of sensing signal.

采用球磨生物炭（BBC）作为导电材料，制备高导电性和目标选择性电极，开发了一种用于超灵敏监测 Pb ²⁺和 Cd ²⁺的新型电化学传感器，以及空腔离子印迹聚合物作为特异性结合部分。通过高温热解和严格的球磨工艺合成纳米级BBC。离子印迹BBC电极由L的原位电聚合构成-在玻璃碳上修饰的 BBC 上的半胱氨酸和模板金属离子，然后去除模板。BBC表现出很强的电子转移能力，并且含有比温和球磨制备的更多的含氧化合物，这归因于形成稳定且富含腔的压印聚合物层和增强传感信号。采用阳极溶解差分脉冲伏安法，该电极可检测极低水平的Pb ²⁺和Cd ²⁺，最低检出限分别为5.86 fM和0.883 aM，线性范围分别为25 fM~1 µM和0.1 fM~1 µM ， 分别。该电极还对其他无关离子和有机化合物具有抗干扰性，并且可以重复使用至少七次而不会降低传感信号。