Nanoneedle electrode

FIGURE 25-38 Detection of dopamme at a multiwall carbon nanolube-based nanoneedle electrode. Differential-pulse voltamrnograms of dopamine at the nanoneedle electrode in various concentrations irom 100 to 1000 pM, Inset is the calibration curve. (From H. Boo et al Anal. Chem., 2006. 78, 617 With permission. Copyright 2006 American Chemical Society ... 

The working curve for the determination of dopamine at a nanoneedle electrode by differential-pulse voltammetry (Figure 25-38) was constructed from the following table of data. 

Nanoneedle electrode, 752 Natural line width, 220-221 Near-fR region, 455 Near-IR spectroscopy. 473-476 Nebulizer... 

In one of the representative work, Patolsky et al. [24] demonstrated the reconstitution of apo-GOx on FAD cofactor electrically contacted to the electrode via single-walled carbon nanotubes (SWCNTs), which act as conductive nanoneedles that electrically wire the enzyme redox-active site to the transducer surface (Fig. 4A). Before immobilisation, the commercially obtained SWCNTs were chemically shortened by treatment with strong acids. The formation of carboxylic (and phenolic) groups at the nanotube ends (and sidewall defect sites) as a result of acid treatment allowed the covalent immobilisation of the SWCNTs on thioethanol/ cysteamine-modified Au electrode in the presence of the coupling reagent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) as depicted in Fig. 4A. The incorporation of 2-thioethanol in the mixed monolayer prevented... 

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