Novel, reagentless, amperometric biosensor for uric acid based on a chemically modified screen-printed carbon electrode coated with cellulose acetate and uricase

Biosensor based on biofilm of L. plantarum has been successfully done for determination of uric acid in human urine compared with colorimetric enzymatic produced relative error of less than 5%. L. plantarum has uricase activity to react with uric acid, to maintain the stability of bacteria forming themselves into biofilms. Magnetite is known to increase sensitivity of the biosensor. The combination of magnetite-polyethylene glycol (Fe3O4-PEG) was used to modify the surface of Screen-Printed Carbon Electrode modified (SPCE) and the resulting modified electrode (biofilm/Fe3O4/PEG/SPCE) displayed good electrocatalytic activity to the oxidation of UA. The composition of biofilms with optical density 1, magnetite 100 mgmL-1 and PEG 3% v / v were able to increase the current up to 48% in 4mM of UA. The biosensor with an optimum composition produced good linearity with a concentration range, limit of detection, limit of quantitation, sensitivity, and repeatability were found to be 0.1 - 4.3 mM, 70 µM, 234 µM, 25.392 µA mM-1, 2.38%, respectively. This biosensor stable up to 49 days of measurement with the remaining activity was 90.70% and selective for interference compounds such as salt, urea, glucose, ascorbic acid. This method has a good stability, sensitivity, and potential application in clinical analysis. Keyword: biofilm, biosensor, L. plantarum, magnetite, uric acid.

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Uric Acid Sensor Based on PEDOT:PSS Modified Screen-Printed Carbon Electrode Fabricated with a Simple Painting Technique

Jurnal Kimia Sains dan Aplikasi ◽

10.14710/jksa.24.2.43-50 ◽

2021 ◽

Vol 24 (2) ◽

pp. 43-50

Author(s):

Wulan Tri Wahyuni ◽

Rudi Heryanto ◽

Eti Rohaeti ◽

Achmad Fauzi ◽

Budi Riza Putra

Keyword(s):

Uric Acid ◽

Electrochemical Sensors ◽

Limit Of Detection ◽

Electrochemical Measurement ◽

Differential Pulse ◽

Carbon Electrode ◽

Layer By Layer ◽

Screen Printed Carbon Electrode ◽

Limit Of Quantitation ◽

Screen Printed

A screen-printed carbon electrode is a suitable electrode for electrochemical sensors due to its simplicity and portability. This study aimed to fabricate a screen-printed carbon electrode modified with poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (SPCE-PEDOT:PSS) to improve the electrochemical performance for uric acid detection. The SPCE was fabricated using a layer-by-layer painting process of conductive ink consisting of graphite as a conductive material, polystyrene as a polymeric binder, and dichloromethane solvent on a polyvinyl chloride paper substrate. The fabricated SPCE was then modified with PEDOT:PSS by a drop-casting method. The characterization of SPCE-PEDOT:PSS surface morphology was performed using the scanning electron microscopy technique. The SPCE-PEDOT:PSS provided an acceptable linearity (R2 = 0.9985, 0.9993, 0.9985), sensitivity (0.070, 0.015, 0.024 µA/µM), precision (%RSD = 2.70%, 2.89%, 2.40%), limit of detection (1.61 µM, 1.14 µM, 1.62 µM), and limit of quantitation (5.37 µM, 3.81 µM to 5.39 µM) in measurement of uric acid standard solution using cyclic voltammetry, amperometry, and differential pulse voltammetry techniques, respectively. The studies using SPCE-PEDOT:PSS indicated that the electrode could be applied in the electrochemical measurement of uric acid in the human urine sample.

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Nanocomposites of poly(l-methionine), carbon nanotube–graphene complexes and Au nanoparticles on screen printed carbon electrodes for electrochemical analyses of dopamine and uric acid in human urine solutions

The Analyst ◽

10.1039/c9an02638j ◽

2020 ◽

Vol 145 (10) ◽

pp. 3656-3665

Author(s):

Yunpei Si ◽

Yae Eun Park ◽

Ji Eun Lee ◽

Hye Jin Lee

Keyword(s):

Uric Acid ◽

Carbon Nanotube ◽

Human Urine ◽

Au Nanoparticles ◽

Carbon Electrodes ◽

Carbon Electrode ◽

Screen Printed Carbon Electrode ◽

Uric Acid Determination ◽

Acid Determination ◽

Screen Printed

A sensitive electrochemical sensor decorated with poly(l-methionine), carbon nanotube–graphene complexes and Au nanoparticles on a screen printed carbon electrode for dopamine and uric acid determination in human urine solution.

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