Ijeri V S, Srivastava A K
Department of Chemistry, University of Mumbai, Santacruz, Maharashtra, India.
Fresenius J Anal Chem. 2000 Jun;367(4):373-7. doi: 10.1007/s002160000411.
The feasibility of fabricating copper-sensitive chemically modified electrodes (CMEs) for trace analysis in aqueous and in 40% (v/v) ethanol-water media was investigated. Carbon paste electrodes modified with crown ethers were constructed by mixing the crown ethers into a graphite powder-paraffin oil matrix. The electrodes so formed were able to bind Cu(II) ions chemically and gave better voltammetric responses than the unmodified ones. The crown ethers studied and compared were 15-crown-5, benzo-15-crown-5 and dibenzo-18-crown-6. With a 3% benzo-15-crown-5 CME, Cu(II) could be quantified at sub-ppm levels by differential pulse voltammetry with a detection limit of 0.05 ppm. By differential pulse anodic stripping voltammetry Cu(II) could be quantified over the range I to 100 ppb. Interference from metal ions like Ni(II), Co(II), Mn(II), Fe(II), etc. have also been studied. The method was successfully applied to artificial as well as commercial samples of alcoholic beverages.
研究了制备用于水相和40%（v/v）乙醇 - 水介质中痕量分析的铜敏感化学修饰电极（CMEs）的可行性。通过将冠醚混入石墨粉 - 石蜡油基质中来构建用冠醚修饰的碳糊电极。如此形成的电极能够化学结合Cu(II)离子，并且比未修饰的电极给出更好的伏安响应。所研究和比较的冠醚有15 - 冠 - 5、苯并 - 15 - 冠 - 5和二苯并 - 18 - 冠 - 6。使用3%苯并 - 15 - 冠 - 5 CME，通过差分脉冲伏安法可在亚ppm水平定量Cu(II)，检测限为0.05 ppm。通过差分脉冲阳极溶出伏安法，Cu(II)可在1至100 ppb范围内定量。还研究了Ni(II)、Co(II)、Mn(II)、Fe(II)等金属离子的干扰。该方法已成功应用于酒精饮料的人工样品和商业样品。
