Niu Xiangheng, Zhao Hongli, Lan Minbo
Shanghai Key Laboratory of Functional Materials Chemistry, and Research Centre of Analysis and Test, East China University of Science and Technology, No. 130 Meilong Road, Shanghai 200237, PR China.
Anal Sci. 2011;27(12):1237-41. doi: 10.2116/analsci.27.1237.
Integrating the advantages of screen printing technology with the encouraging electroanalytical characteristic of metallic bismuth, we developed an ultrasensitive and disposable screen-printed bismuth electrode (SPBE) modified with multi-walled carbon nanotubes (MWCNTs) for electrochemical stripping measurements. Metallic bismuth powders and MWCNTs were homogeneously mixed with graphite-carbon ink to mass-prepare screen-printed bismuth electrode doped with multi-walled carbon nanotubes (SPBE/MWCNT). The electroanalytical performance of the prepared SPBE/MWCNT was intensively evaluated by measuring trace Hg(II) with square-wave anodic stripping voltammetry (SWASV). The results indicated that the SPBE modified with 2 wt% MWCNTs could offer a more sensitive response to trace Hg(II) than the bare SPBE. The stripping current obtained at SPBE/MWCNT was linear with Hg(II) concentration in the range from 0.2 to 40 µg/L (R(2) = 0.9976), with a detection limit of 0.09 µg/L (S/N = 3) under 180 s accumulation. The proposed "mercury-free" electrode, with extremely simple preparation and ultrahigh sensitivity, holds wide application prospects in both environmental and industrial monitoring.
我们将丝网印刷技术的优势与金属铋令人鼓舞的电分析特性相结合，开发了一种用于电化学溶出测量的、用多壁碳纳米管（MWCNT）修饰的超灵敏一次性丝网印刷铋电极（SPBE）。将金属铋粉和多壁碳纳米管与石墨 - 碳油墨均匀混合，批量制备掺杂多壁碳纳米管的丝网印刷铋电极（SPBE/MWCNT）。通过方波阳极溶出伏安法（SWASV）测量痕量Hg(II)，对制备的SPBE/MWCNT的电分析性能进行了深入评估。结果表明，用2 wt%多壁碳纳米管修饰的SPBE对痕量Hg(II)的响应比裸SPBE更灵敏。在SPBE/MWCNT上获得的溶出电流与Hg(II)浓度在0.2至40 µg/L范围内呈线性关系（R(2) = 0.9976），在180 s富集下检测限为0.09 µg/L（S/N = 3）。所提出的“无汞”电极制备极其简单且灵敏度超高，在环境和工业监测中具有广阔的应用前景。
