Electrochemical Detection of Uric Acid Based on a Carbon Paste Electrode Modified with Ta₂O₅ Recovered from Ore by a Novel Method

Abstract

Except for well-known commercial production procedures, this study demonstrates that Ta 2 O 5 particles can be produced. Through a series of steps, highly pure Ta 2 O 5 particles (99.45%) were produced from the raw ore. We have electrochemically detected one of the important nitrogenous compounds present in urine, “uric acid”, by a Ta 2 O 5 particle-modified carbon paste electrode (Ta 2 O 5 -MCPE) using cyclic voltammetry. The prepared electrode has shown excellent current sensitivity at a pH of 6.0 phosphate-buffered solution. We have found that 4 mg Ta 2 O 5 -MCPE has recorded the highest current sensitivity of 75.75 μA. The oxidation peak current was varied with the uric acid concentration in the range from 1 to 5 mM at 4 mg Ta 2 O 5 -MCPE. We have calculated the electrode-active surface area for a bare carbon paste electrode and 4 mg Ta 2 O 5 -MCPE using the Randles–Sevcik equation, and the values were found to be 0.0202 and 0.0450 cm 2 , respectively. On the other hand, the calculated values of limit of detection and limit of quantification were reported as 0.5937 × 10 –8 M and 1.9791 × 10 –8 M, respectively, for the prepared 4 mg Ta 2 O 5 -MCPE. The interfere studies revealed that the variation in the electrochemical signal of uric acid in the presence of different metal ions was found to be less than ±5%.

Review—Electrochemical Sensing of Uric Acid: Methods and Recent Materials

“…Although the type of bioreceptor used for UA sensing is essential, other factors that seem to be trivial such as -the type of substrate used (glassy carbon electrode, nickel foam, carbon paste electrode, carbon cloth, carbon paper), geometrical area of the working electrode, thickness of the coating on the modified electrode, concentration and type of binder used to coat the active sensing material also contribute to the overall device performance. [26][27][28][29] The Electrochemical detection techniques used in uric acid detection mostly related to bio-chemistry of the sensing analyte and its interaction with the sensor. In bio-electrochemistry, the reaction under study would either generate a measurable potential or charge accumulation (potentiometric), generate a measurable current (amperometric) or it might alter the conductive properties (conductometric) of the medium measured between the electrodes.…”

Advances in electrochemical biosensors employing carbon-based electrodes for detection of biomarkers in diabetes mellitus

“…The reaction rate is controlled by mass transfer (diffusion) [ 96 ]. In diffusion-controlled processes, the peak current ( i p ) is proportional to the square root of the scan rate ( v 1/2 ) as described by the Randles-Ševčik equation (1) [ 97 ]:…”

Self-powered sensing platform for monitoring uric acid in sweat using cobalt nanocrystal-graphene quantum dot-Ti3C2TX monolithic film electrode with excellent supercapacitor and sensing behavior

“…The nanomaterials used in electrochemical detection of uric acid mainly include metal nanocrystal such as Fe [10], metal oxide such as Ta 2 O 5 [11], 2D material such as graphene [12] and MXene [13]. Metal nanocrystal has a high conductivity, but it is prone to combine with electroactive analyte and produce a serious memory effect unless noble metal nanocrystal.…”