Uric acid

Hydride chloride (37 weight percent, wt%), ethanol, nitromethane, sodium hydroxide, glacial acetic acid, hydrogen peroxide solution (30 wt%), L-ascorbic acid (AA), uric acid (UA), L-cysteine (Cys), and glutathione (GSH) were purchased from Sinopharm Chemical Reagent Co. Ltd. (Shanghai, China, www.en.reagent.com.cn). Sodium acetate anhydrous was purchased from Sigma-Aldrich Chemical Co., Ltd. (St. Louis, MO, USA, www.sigmaaldrich.com/united-states.html). 2-(tert-butoxycarbonyl)-2-methyl-3,4-dihydro-2H-pyrrole 1-oxide (BMPO) was purchased from ApexBio Technology. (7505 Fannin street, Suite 410, Houston, USA, www.apexbt.com). Pd(CH₃CN)₂Cl₂, ammonium hydroxide solution (25–28 wt%), 3,3′,5,5′-tetramethylbenzidine (TMB), silicon (IV) oxide, ammonium persulfate (APS), aniline, dimethyl sulfoxide (DMSO), potassium thiocyanate (KSCN), (±)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid and DL-homocysteine (Hcy) were purchased from Shanghai Titan Scientific Co., Ltd. (Shanghai, China, www.tansoole.com). All chemicals were used as received without any further purification.

Potassium chloride (KCl), sodium chloride (NaCl), sodium sulphate (Na₂SO₄), dibasic sodium phosphate (Na₂HPO₄), potassium dihydrogen phosphate (KH₂PO₄), and Uric acid (UA) were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). Dopamine (DA) was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. (Shanghai, China). All of the above chemical reagents were analytical reagents and were used without further purification. GO powder and rGO water dispersion were purchased from Nanjing JCNANO Technology Co., Ltd. (Nanjing, China). Ti₃C₂T_x water dispersion was purchased from Beike 2D materials Co., Ltd. (Suzhou, China). Deionized Milli-Q water (18.2 MΩ/cm) was used throughout the experiments.

Polyacrylonitrile (PAN) (molecular weight (Mw) = 150,000), sodium hydroxide (NaOH), cupric acetate monohydrate (Cu(CH₃COO)₂·H₂O), sodium chloride (NaCl), cobalt(II) acetate tetrahydrate (Co(CH₃COO)₂·4H₂O), d-glucose, ascorbic acid (AA), uric acid (UA), l-lysine, dopamine (DA), and N,N-dimethylformamide (DMF) were provided by Sinopharm Chemical Reagent Corporation (China). Nafion (5 wt.%) was obtained from Sigma-Aldrich. Thiophene, thiophene-3-boronic acid monolayer acid (TBA), and sodium fluoride (NaF) were purchased from Macklin Chemical Reagent Corporation (Shanghai, China).

Quartz glass (SiO₂) of size of 10 × 5 × 0.5 mm was purchased from Hefei Kejing Crystal Technology CO., LTD (Hefei, China). Hydrogen (H₂), methane (CH₄), carbon tetrafluoride (CF₄), nitrogen (N₂) and argon (Ar) gases with 99.99% purity were all purchased from Jinan Deyang Special Gas Company (Jinan, China). Hydrogen peroxide (H₂O₂) with a 30% mass fraction, acetone (CH₃COCH₃), sulfuric acid (H₂SO₄, with a 98% mass fraction), sodium dihydrogen phosphate dihydrate (NaH₂PO₄·2H₂O), disodium hydrogen phosphate (Na₂HPO₄), ascorbic acid (AA), dopamine (DA) and uric acid (UA) were purchased from Sinopharm Chemical Regent Company (Shanghai, China). Phosphate buffer solution (0.1 mol L⁻¹, pH = 7.2) was a mixture of NaH₂PO₄ solution (0.1 mol L⁻¹) and Na₂HPO₄ solution (0.1 mol L⁻¹). All reagents used in the experiments were of analytical grade and used without further purification process. Deionized water with a resistivity of 18.25 MΩ cm was used in all aqueous solutions.

HITP·6HCl (Chemical Reagent) were brought from Shanghai TenSus Biotechnology Co., Ltd. NiCl₂·6H₂O (Analytical Reagent) and Nafion (5% solution) was brought from Sigma-Aldrich. Potassium hexacyanoferrate (K₄Fe(CN)₆), triethylamine, glucose, KCl, KOH, uric acid (UA), and ascorbic acid (AA) of an analytical reagent were purchased from Sinopharm Chemical Reagent Co., Ltd. All chemicals were of an analytical reagent grade and were used without further purification. All solutions were prepared by distilled water and stored at room temperature.

Co(CH₃COO)₂·4H₂O, Ni(CH₃COO)₂·4H₂O, 4,4′-biphenyldicarboxylic acid (H₂BPDC), 2,6-naphthalenedicarboxylic acid (H₂NDC), 1,4-benzenedicarboxylic acid (H₂BDC), KOH, NaOH, KCl, ascorbic acid (AA), uric acid (UA), dopamine (DA), glucose, Ethanol, and N,N-Dimethylformamide (DMF) were bought from Sinopharm Chemical Reagent (Shanghai, China). Pure water (15 MΩ) used in the experiments was supplied by a Millipore System (Milli Q). Human serum was provided by the Second Affiliated Hospital of Hubei University of Science and Technology.