Simultaneous electrochemical determination of ascorbic acid, dopamine and uric acid using a palladium nanoparticle/graphene/chitosan modified electrode

Sensitive and Profitable Electrochemical Detection of Uric Acid in the Presence of Dopamine with a Novel Carbon Paste Electrode Decorated with a Copper(II) Complex

“…Therefore, these results indicate that the increase in the surface area of the electrode decorated with Cu C might have increased the concentration of UA on the surface of the electrode, in addition to showing a particular selectivity for UA over DP. On the other hand, the oxidation potential of UA was observed at lower positive potential values of 0.5 V than previously reported [14,17,36,37] in studies where more complex electrodes with Cu, Ag, Pd and Pt metal ions were used. This result indicates that this composite requires less energy for UA oxidation.…”

“…Values of the parameters used to fit the impedance results using the electrical circuit shown in the inset of Figure 1B. replaced by the current exchange (I 0 ) [35] where I 0 = 7.14 × 10 À 6 mA [36]. As seen in Table 1, the diffusion resistance of the Cu C /CPE is almost half of that exhibited by the CPE.…”

Fabrication of metal–organic single crystalline nanowires and reduced graphene oxide enhancement for an ultrasensitive electrochemical biosensor

“…As shown in Fig. 22 Furthermore, specificity is another important factor to evaluate a biosensor. Under optimal conditions, the oxidation peak current (I pa ) of DA increased linearly with the increase of DA concentration in the range from 0.001 mM to 25 mM and 25 mM to 200 mM (inset of Fig.…”

“…3 It is important to fabricate a chemically modified electrode for the detection of DA with high selectivity and sensitivity. In previous studies, various metal-phthalocyanine powder composites have been applied as chemiresistive gas sensors 17,18 and biosensors, [19][20][21][22][23] because of their distinguished merits such as low cost, endurance, high sensitivity, high stability and good reliability. However, physiological levels of DA range from nanomolar to low micromolar, and the current electrochemical sensors of DA are not only complicated due to their nanomaterial synthesis and sensor preparation, but also the current electrochemical sensors suffer from limited sensitivity and specificity toward DA.…”

A sensitive and selective chemosensor for ascorbic acid based on a fluorescent nitroxide switch

“…Zhang et al [18] fabricated an electrochemical sensor for selective detection of ascorbic acid in the presence of dopamine and uric acid by modifying the glassy carbon electrode with carbon-supported NiCoO 2 (NiCoO 2 /C) nanoparticles. Wang et al [19] prepared a palladium nanoparticle/graphene/chitosan/glassy carbon electrode which displayed excellent electrochemical catalytic activities towards ascorbic acid, dopamine and uric acid. But these methods have relatively high detection limit towards ascorbic acid.…”