Catalytic capability of poly(malachite green) films based electrochemical sensor for oxidation of dopamine

Electrochemical studies of dopamine under stagnant and convective conditions at a sensor based on gold nanoparticles hosted in poly(triaminopyrimidine)

“…The average apparent diffusion coefficient of DA ( app DA D ) is 6.07 ×10 5 cm 2 s 1calculated from the slope of the Sevcik-Randles relationship given above in equation(3), taking into consideration that n = 2, A = 0.071 cm 2 and C = 0.3 mM. The calculated value is consistent with the 6.50 ×10 5 cm 2 s 1 reported for DA oxidation at poly(malachite green) film modified GCE[24] by CV method. It also describes the diffusion of a small biological molecule in a binary system that includes the effects on the mass transport process.…”

“…Approximately 2000 times greater than 1.83 × 10 5 cm s 1 reported at poly(malachite green) film [24], and it is several decades greater than 6.30 × 10 4 cm s 1 reported at palladium hexacyanoferrate film [33]. The above large differences may conclude a fast electron transfer process pertinent to the stable and conductive surface materials made of AuNPs hosted in PTAP matrix.…”

“…For many literature values, the heterogeneous rate constant measured at modified electrodes [24,29,33] given in (cm 3 [29]. Approximately 2000 times greater than 1.83 × 10 5 cm s 1 reported at poly(malachite green) film [24], and it is several decades greater than 6.30 × 10 4 cm s 1 reported at palladium hexacyanoferrate film [33].…”

The role of bromine adlayer at palladium electrode in the electrochemical oxidation of dopamine in alkaline solution

“…The resulting slope was used to calculate the diffusion coefficient of DA (D DA ) which apparently equal to 1.37 Â 10 À8 m 2 s À1 . This value is somewhat higher than those reported in the literature [60][61][62][63], a summary of which is presented in Table 2.…”

Conducting polymers in chemical sensors and arrays

“…However, differences in the redox behavior and specific chemical interactions allow one to get required selectivity for several particular analytes. For example, voltammetric detection of redox active compounds was used for the detection of dopamine [52,245,246,[272][273][274], ascorbic acid [245,272,273,[275][276][277], uric acid [246], NADH [218,278], morphine [248], serotonin [249]. The advantage of CP modified electrodes over conventional metal or GCE electrodes is provided by the electrocatalytic ability of some CP.…”