Oxidative peak currents, poly

Both of the P(V)TPP derivatives (b) and (c) (Figure 5) were polymerized by electrochemical oxidation to give polymers, whereas (a) was scarcely polymerized. (Figure 6 (A)). Consequently, poly-(b) and poly-(c), 1 D porphyrin arrays, were electrochemically deposited on the ITO electrode at potentials >1.2V and 0.9V (vs. SCE), respectively. The peak current observed around -0.4V, which was assigned to the redox reaction of the P(V)TPP moieties, increased and thus signaled the deposition of the porphyrin polymer onto the electrode. 

It was observed that the anodic peak current of Fc was enhanced in the presence of the [FeCCbOg] " " redox probe. This effect was rationalized by a possible communication between the [FeCCbOg] " redox probe in close proximity to the Fc/Fc couple. Thus, the oxidation Fc- Fc + e is followed by a reduction process which involves [Fe(CN)g] , and which allows another reduction process to the Fc to continue the CV cycle. Similar observations have been reported for immobilized Fc-peptides and Fc-functionalized poly(propylene imine dendrimers [41,42]. The differential in the... 

The diffusion coefficient of CIO4 in poly(vinylferrocene) films has been found to increase modestly with voltage to the peak current region where there is an equal concentration of oxidized and reduced sites [102]. At low oxidation levels, poly(pyrrole) and other electronically conducting polymers have low conductivities of the same order as redox polymers. The latter reported that the diffusivity of BF4 increased from 1 x 10" to 3.4 X 10" cm s" as the level of oxidation was increased [123]. This same trend was noted earlier for poly(3-methylthiophene) films where the diffusivity was found to increase with oxidation level by an order of magnitude in... 

Palladium nanoparticles (PdNPs) have high catalytic activity toward analytes, such as hydrazine. Fig. 37 [138]. The hydrazine oxidation peak was observed at +0.14 V and -0.28 V (in 1 mM hydrazine) on poly-CoTAPc-GCE (Fig. 37a) and PdNPs deposited on polymerized CoTAPc-GCE (PdNPs/poly-CoTAPc-GCE, Eig. 37b), with background corrected currents of 36 and 60 pA, respectively, at 1 mM hydrazine. PdNPs/poly-CoTAPc-GCE shows the largest currents for hydrazine oxidation of 60 pA and the least positive potential for hydrazine oxidation, showing the importance of combining the Pc with PdNPs. 

A sensor for the determination of calcium dohesilate, a drug used for the treatment of hlood vessels, was fabricated by CV from a solution containing o-phenylenediamine, MWCNT and sodium dodecylbenzene-sulfonate [57]. The composite material of poly(o-phenylenediamine] [PoPD] and MWCNTs had larger effective surface area compared to the neat PoPD, and the peak oxidation current for calcium dohesilate was two times higher than the sum of the currents on the plain MWCNT and the PoPD electrodes. 

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