Spectrophotometric detection of uric acid with enzyme-like reaction mediated 3,3′,5,5′-tetramethylbenzidine oxidation

Abstract

ABSTRACT. WO3 nanosheets (NSs) were prepared and characterized by X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The obtained WO3 NSs exhibited peroxidase-like catalytic activity, which can catalyze H2O2 to oxidize 3,3 ',5,5 '-tetramethylbenzidine (TMB) to generate oxidized TMB (oxTMB) with an absorption peak centered at 652 nm. Based on this, a facile method for the spectrophotometric determination of H2O2 was established. Under the selected conditions, the increase in absorbance of oxTMB enabled the detection of H2O2 ranging from 2.0 to 180 μM. Considering the fact that H2O2 is one of the products of urate oxidase (UAO)-catalyzed uric acid (UA) oxidation, a convenient method for the selective determination of UA was further developed with the help of UV–vis spectrophotometer. The increase of absorbance at 652 nm showed a linear response to UA concentration over the range of 2.0–180 μM. The limit of detection for UA was as low as 1.25 μM. More importantly, the proposed method was applied to the determination of UA in serum samples with satisfactory results.
 
 KEY WORDS: Spectrophotometric, WO3 nanosheets, Uric acid, Determination
 
 Bull. Chem. Soc. Ethiop. 2023, 37(1), 11-21. 
 DOI: https://dx.doi.org/10.4314/bcse.v37i1.2

Smartphone based colorimetric approach for quantitative determination of uric acid using Image J

“… Colorimetric method principle Linearity range Sample Detection mode Comment Reagents References Complexion with potassium ferricyanide, and ferric chloride 2–200 μg·mL −1 Urine and serum Blue colored complex measured at maximum wavelength 752 nm – HCl pps = 2 (signal word danger and one hazard pictogram) Potassium ferricyanide pps* = 2 (warning and two pictogram) Ferric chloride pps = 4 (danger and two pictogram) 31 MIL-53 Fe as a colorimetric sensor 0.75–10 μg.mL −1 (4.5–60 μM) Urine and serum Blue colored product measured at maximum wavelength 652 nm Synthesis of this metal organic frame work requires heating for 17 h and 24 h drying Solvent DMF pps = 6 (danger and three pictogram) Ferric chloride pps = 4 32 AgNPs as a colorimetric sensor 0.0168 ng·mL −1 16.8 μg·mL −1 (0.1 nM–0.1 mM) Spiked serum samples Color change of the solution from brown to yellow. In parallel, the absorbance is blue shifted from 477 to 428 nm Synthesis of silver nanoparticles require stirring for 1 h at 95 °C Silver nitrate pps = 6 (danger and three pictogram) 33 WO 3 NSs as a colorimetric sensor 0.33–30 μg·mL −1 (2–180 µM) Serum Blue color measured at maximum wavelength 652 nm Synthesis of nano sheets require magnetic stirring for 72 h and drying for 12 h Sodium tungsten oxide dihydrate (Na 2 WO 4 ·2H 2 O) pps* = 1 (warning and one ictogram) Solvent HNO 3 pps* = 2 (danger and one pictogram) 34 Phosphotungestate 3–15 μg·mL −1 Urine …”

“…Furthermore, two other reported methods involve the utilization of metal–organic framework MIL-53(Fe) and WO 3 Nanosheets. Despite their high sensitivity, the synthesis of these materials is complex, time-consuming, and necessitates the use of non-green solvents, along with requiring extensive chemical and physical characterization 32 , 34 . Another method involving silver nanoparticles, while simpler and faster than the former two, still involves multiple procedures, non ecofriendly reagents, and characterization steps 33 .…”

“…Different chromatographic methods have been developed for determination of uric acid and creatinine in human urine 28 – 30 . In addition, several colorimetric methods have been recently reported 31 – 34 . In this study, we have applied DIC using Image J for quantitative determination of uric acid after treatment with phosphotungstate reagent in alkaline medium to develop a blue color.…”