MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Chemistry. 2010 Apr 6;16(13):4120-6. doi: 10.1002/chem.200902874.
A water-insoluble picket-fence porphyrin was first assembled on nitrogen-doped multiwalled carbon nanotubes (CN(x) MWNTs) through Fe--N coordination for highly efficient catalysis and biosensing. Scanning electron micrographs, Raman spectra, X-ray photoelectron spectra, UV/Vis absorption spectra, and electrochemical impedance spectra were employed to characterize this novel nanocomposite. By using electrochemical methods on the porphyrin at low potential in neutral aqueous solution, the presence of CN(x) MWNTs led to the direct formation of a high-valent iron(IV)-porphyrin unit, which produced excellent catalytic activity toward the oxidation of sulfite ions. By using sulfite ions, a widely used versatile additive and preservative in the food and beverage industries, as a model, a highly sensitive amperometric biosensor was proposed. The biosensor showed a linear range of four orders of magnitude from 8.0x10(-7) to 4.9x10(-3) mol L(-1) and a detection limit of 3.5x10(-7) mol L(-1) due to the highly efficient catalysis of the nanocomposite. The designed platform and method had good analytical performance and could be successfully applied in the determination of sulfite ions in beverages. The direct noncovalent assembly of porphyrin on CN(x) MWNTs provided a facile way to design novel biofunctional materials for biosensing and photovoltaic devices.
一种不溶于水的栅栏型卟啉首先通过 Fe-N 配位组装在氮掺杂多壁碳纳米管（CN(x)MWNTs）上，用于高效催化和生物传感。采用扫描电子显微镜、拉曼光谱、X 射线光电子能谱、紫外可见吸收光谱和电化学阻抗谱对这种新型纳米复合材料进行了表征。在中性水溶液中，通过在低电位下对卟啉进行电化学方法，CN(x)MWNTs 的存在导致高价铁(IV)-卟啉单元的直接形成，从而对亚硫酸盐离子的氧化产生了优异的催化活性。通过使用亚硫酸盐离子作为模型，亚硫酸盐离子是食品和饮料工业中广泛使用的多功能添加剂和防腐剂，提出了一种高灵敏度的安培生物传感器。由于纳米复合材料的高效催化作用，该生物传感器在 8.0x10(-7) 到 4.9x10(-3) mol L(-1) 的四个数量级范围内呈现线性范围，检测限为 3.5x10(-7) mol L(-1)。该设计平台和方法具有良好的分析性能，可成功应用于饮料中亚硫酸盐离子的测定。卟啉在 CN(x)MWNTs 上的直接非共价组装为设计用于生物传感和光伏器件的新型生物功能材料提供了一种简便的方法。
