Nanotechnology Innovation Centre, Advanced Materials Division, Mintek, Private Bag X3015, Randburg 2125, South Africa.
Talanta. 2011 Sep 30;85(4):2202-11. doi: 10.1016/j.talanta.2011.07.069. Epub 2011 Jul 27.
The pre-grafted screen-printed gold electrode modified with phenyl-amino monolayer was investigated for covalent immobilization of phenyl-amine functionalized single-walled carbon nanotubes (PA-SWCNT) and metal tetra-amino phthalocyanine (MTAPc) using Schiff-base reactions with benzene-1,4-dicarbaldehyde (BDCA) as cross-linker. The PA-SWCNT and MTAPc modified electrodes were applied as hybrids for electrochemical sensing of H(2)O(2). The step-by-step fabrication of the electrode was followed using electrochemistry, impedance spectroscopy, scanning electron microscopy and Raman spectroscopy and all these techniques confirmed the fabrication and the immobilization of PA-SWCNT, MnTAPc and CoTAPc onto gold surfaces. The apparent electron transfer constant (k(app)) showed that the carbon nanotubes and metallo-phthalocyanines hybrids possess good electron transfer properties compared to the bare, pre-grafted and the MTAPc modified gold electrode surfaces without PA-SWCNT. The electrochemical sensing of hydrogen peroxide was successful with PA-SWCNT-MTAPc hybrid systems showing higher electrocatalytic currents compared to the other electrodes. The analytical parameters obtained using chronoamperometry gave good linearity at H(2)O(2) concentrations ranging from 1.0 to 30.0 μmol L(-1). The values for the limit of detection (LoD) were found to be of the orders of 10(-7)M using the 3δ for all the electrodes. The PA-SWCNT-MTAPc modified SPAuEs were much more sensitive compared to PA-MTAPc modified SPAuEs.
经苯二甲醛(BDCA)作为交联剂的席夫碱反应,研究了预接枝的金电极上苯基-氨基单层修饰的苯氨基功能化单壁碳纳米管(PA-SWCNT)和金属四氨基酞菁(MTAPc)的共价固定化。将 PA-SWCNT 和 MTAPc 修饰电极用作电化学传感 H2O2 的混合体。采用电化学、阻抗谱、扫描电子显微镜和拉曼光谱等技术对电极的逐步制备进行了跟踪,所有这些技术都证实了 PA-SWCNT、MnTAPc 和 CoTAPc 被固定在金表面上。表观电子转移常数(kapp)表明,与裸金、预接枝金和无 PA-SWCNT 的 MTAPc 修饰金电极表面相比,碳纳米管和金属酞菁混合体具有良好的电子转移特性。PA-SWCNT-MTAPc 混合体系对过氧化氢的电化学传感是成功的,与其他电极相比,其电化学催化电流更高。计时电流法得到的分析参数在 H2O2 浓度范围为 1.0 至 30.0 μmol L-1 时具有良好的线性。对于所有电极,检测限(LoD)的值均为 10-7M 左右。与 PA-MTAPc 修饰 SPAuEs 相比,PA-SWCNT-MTAPc 修饰 SPAuEs 更加敏感。