Electrochemical properties of the hexacyanoferrate(II)–ruthenium(III) complex immobilized on silica gel surface chemically modified with zirconium(IV) oxide

Construction of a New Sensor with Ruthenium Complex Anchored in Functionalized Silica and Their Application in Determination of Ascorbic Acid in Industrial Fruit Juice

“…It was also observed that the ion, independent of the hydrated radius, could compensate the charge. A similar behavior was also observed in hexacyanoferrate (II)-ruthenium (III) complex immobilized on silica gel surface chemically modified with zirconium (IV) oxide [25]. With this electrode, it was made a study about the oxidation of ascorbic acid, using differential pulse voltammetry, in conditions of 25 mV amplitude and 7.8 mV s -1 ) (-0.8 to 1.2 V) vs Ag/AgCl), phosphate buffer, pH = 6.86, µ= 0.10 mol dm -3 , 298 K. The Figure 2 shows the differential pulse voltammograms of the carbon paste electrode modified with SF-3APTS/EDTA/Ru(EDTA) with the addition of ascorbic acid, the anodic peak current increased significantly, when compared with that obtained at the modified carbon paste electrode.…”

Construction of a New Sensor with Copper(II) Complex Anchored in Calcium Phosphate Intercalated with m-Aminobenzoic Acid and Their Application in Determination of Dopamine

“…Such result reflects that kinetics of electron transfer on the electrode surface is not enough fast, as a consequence of having a matrix with considerable resistance. The correlation of the peak current, I pa and I pc , against v 1/2 (v is the scan rate) is linear, which is very similar to a diffusion controlled process [24]. Since the electroactive species strongly adheres to the matrix, as it was shown earlier, the mechanism may be explained by ion transport of the supporting electrolyte from electrode surface for charge compensation [25].…”

Construction of new sensors with copper and cobalt com¬ple¬xes anchored on organofunctionalized silica and their use for electrocatalytic oxidation of reagents of biological interest

“…This result reflects the kinetics of electron transfer on the electrode surface, which is not fast enough, as a consequence of having a matrix with considerable resistance. The graphs of anodic peak current as a function of the square root of scan rate and anodic peak current as a function of scanning rate (not shown here) presented linear behavior, which suggests a diffusion-controlled process [16,17]. Since it was shown earlier that electroactive species strongly adhere to the matrix, the mechanism may be explained by the transport of the ion of supporting electrolyte from the electrode surface for charge compensation [18,19].…”