A novel electrocatalytic platform for separation of the overlapping voltammetric responses of AA, DA and UA

Novel UIO-66-NO2@XC-72 nanohybrid as an electrode material for simultaneous detection of ascorbic acid, dopamine and uric acid

“…2a, the bare electrode has a pair of reversible redox peaks (i pa ¼ 24.98 mA, i pc ¼ À21.58 mA, DE p ¼ 0.18 V), while the UIO-66-NO 2 /GCE sensor exhibits a broadened peak potential and small peak current, suggesting that the sensor surface is blocked due to the poor electron transfer of UIO-66-NO 2 material. 48 It is also investigated by EIS measurements that the electron transfer kinetics occur at the interface of electrode/electrolyte (Fig. 2c).…”

“…2c). 51 The distinct semicircle curve at high frequencies reects the ability of electron transfer (R ct ) of different sensors 47,48 and the smaller diameter of R ct represents higher electron transfer at the interface of electrode/electrolyte. 49,52 The R ct values increase in the order of the XC-72/GCE sensor < UIO-66-NO 2 @XC-72/GCE sensor < bare GCE < UIO-66-NO 2 /GCE sensor.…”

“…When XC-72 and UIO-66-NO 2 @XC-72 modied electrode surface, the DE p values decline to 0.16 and 0.15 V, respectively. The XC-72/GCE (i pa ¼ 32.88 mA, i pc ¼ À31.11 mA) and UIO-66-NO 2 @XC-72/GCE sensors (i pa ¼ 30.65 mA, i pc ¼ À29.81 mA) possess higher current, and smaller DE p proles, indicating that XC-72 possesses good electronic conductivity and is benecial to electron transfer [48][49][50]. When 5.0 mM Ru(NH 3 ) 6 Cl 3 was added into 0.1 M KCl solution, the similar results can be obtained fromFig.…”

Electrochemical Molecular Imprinted Sensors Based on Electrospun Nanofiber and Determination of Ascorbic Acid

“…18 As such, many scientists devote a great deal of attention to the separation of AA, DA and UA with some novel nanomaterials in electrochemistry, because of this approximative oxidation potential. [19][20][21][22][23] In our previous work, the simultaneous detection of AA and UA was developed with nanostructured gold, due to their high electrocatalytic activities toward the oxidation of AA and UA. 24 In this work, we investigated the possibility of preparing electrospun nanofibers that contain molecularly imprinted binding sites.…”

A Nicotinamide Adenine Dinucleotide Dispersed Multi-walled Carbon Nanotubes Electrode for Direct and Selective Electrochemical Detection of Uric Acid

“…7,8 Compared with other described methods, electrochemical analysis based on the electrooxidation of UA on an electrode surface has been shown to be very promising because it is a highly selective, cheaper and a more rapid method. [9][10][11][12] However, dopamine (DA), UA and ascorbic acid (AA), with very similar electrochemical properties, always coexist in the extra cellular fluids of the central nervous system and serum in mammals, and there have an overlapping oxidation potential on many electrodes, resulting in poor sensitivity and selectivity. In order to improve the selectivity, a variety of modified electrodes were recently designed and constructed to either reduce the overpotential of AA and DA oxidation or prevent the approach of AA and DA to the electrode surface.…”