Moretto Ligia Maria, Pepe Niki, Ugo Paolo
Department of Physical Chemistry, Università Cà Foscari di Venezia, Calle Larga S.Marta 2137, Venezia I-30123, Italy.
Talanta. 2004 Apr 19;62(5):1055-60. doi: 10.1016/j.talanta.2003.10.024.
Gold nanoelectrodes ensembles (NEEs) have been prepared by electroless plating of Au nanoelectrode elements within the pores of a microporous polycarbonate template membrane. Cyclic voltammograms recorded in (ferrocenylmethyl) trimethylammonium hexafluorophosphate (FA(+) PF(6)(-)) solutions showed that these NEEs operate in the "total-overlap" response regime, giving well resolved peak shaped voltammograms. Experimental results show that the faradaic/background currents ratios at the NEE are independent on the total geometric area of the ensemble, so that NEE can be enlarged or miniaturized at pleasure without influencing the very favorable signal/noise ratio. Differential pulse voltammetry (DPV) at the NEE is optimized for direct determinations at trace levels. DPV at NEE allowed the determination (with no preconcentration) of trace amounts of FA(+), with a detection limit of 0.02muM. The use of NEE and DPV in cytochrome c (cyt c) solutions showed the possibility to observe the direct electrochemistry of submicromolar concentration of the protein, even without the need of adding any promoter or mediator.
通过在微孔聚碳酸酯模板膜的孔内化学镀金纳米电极元件制备了金纳米电极阵列（NEEs）。在（二茂铁基甲基）三甲基氯化铵六氟磷酸盐（FA(+) PF(6)(-)）溶液中记录的循环伏安图表明，这些NEEs在“完全重叠”响应模式下运行，给出了分辨良好的峰形伏安图。实验结果表明，NEE处的法拉第/背景电流比与阵列的总几何面积无关，因此可以随意扩大或缩小NEE，而不会影响非常有利的信噪比。NEE处的差分脉冲伏安法（DPV）针对痕量水平的直接测定进行了优化。NEE处的DPV允许（无需预浓缩）测定痕量的FA(+)，检测限为0.02μM。在细胞色素c（cyt c）溶液中使用NEE和DPV表明，即使不需要添加任何促进剂或介质，也有可能观察到亚微摩尔浓度蛋白质的直接电化学。
