Electrochemical Urea Biosensing Techniques

Electrochemical urea biosensors employ potentiometric, amperometric or impedimetric readouts to convert the presence of urea into an electrical signal. Enzyme-based devices typically immobilise urease on nanostructured electrodes or polymer membranes, where enzymatic hydrolysis of urea generates ionic by-products that shift local pH or ionic conductivity. Non-enzymatic approaches exploit electrocatalytic materials—such as metal and metal-oxide nanoparticles, carbon nanotube hybrids or conducting polymers—to oxidise urea directly, thereby avoiding enzyme-related stability issues. Advances in surface nanostructuration, microfabrication and integration with portable electronics have driven improvements in sensitivity, selectivity and response time. Artificial-intelligence-assisted algorithms are now being explored to distinguish urea signals from interferents and to automate calibration. Together, these developments are paving the way for robust, low-cost devices applicable to point-of-care renal diagnostics, continuous haemodialysis monitoring, agricultural nutrient management and environmental water analysis.

Research from Nature Portfolio

Recent studies have refined non-enzymatic sensing through the integration of mixed metal oxide nanocomposites on printable electrodes. One report demonstrated a screen-printed electrode modified with a CuO/Co₃O₄@multi-walled carbon nanotube composite, achieving picomolar sensitivity, a broad linear range from 10⁻¹² to 10⁻² M and high selectivity in real urine and serum samples by means of impedance spectroscopy. Another investigation converted commercial glucose test strips into portable urea detectors by electrochemically depositing silver nanoparticles onto enzyme-free channels; the resulting amperometric platform delivered a low-millimolar detection limit compatible with physiological urea levels and exhibited excellent reproducibility, storage stability and resistance to common biological interferents.

Electrochemical Urea Biosensing Techniques publication trend

The graph below shows the total number of articles in electrochemical urea biosensing techniques across all publications each year (not limited to Nature Index journals).

Technical terms

Cyclic voltammetry: An electrochemical method in which electrode potential is swept linearly and resulting current is measured to characterise redox processes.

Electrochemical impedance spectroscopy (EIS): A technique applying an alternating potential over a frequency range to probe interfacial charge transfer and mass-transport phenomena.

Screen-printed electrode (SPE): A low-cost, mass-producible electrode platform fabricated by printing conductive inks onto substrates for disposable sensing.

Non-enzymatic sensor: A device that detects analytes via direct electrocatalytic oxidation or reduction on modified electrodes, without biological catalysts.

Linear range: The analyte concentration interval over which sensor response is directly proportional to concentration.

Detection limit: The lowest analyte concentration distinguishable from baseline noise with defined confidence.

References

1. Electrochemical methods for the determination of urea: Current trends and future perspective. TrAC Trends in Analytical Chemistry (2023).
2. Non-Enzymatic Electrochemical Detection of Urea on Silver Nanoparticles Anchored Nitrogen-Doped Single-Walled Carbon Nanotube Modified Electrode. Journal of The Electrochemical Society (2018).
3. An AgNP-deposited commercial electrochemistry test strip as a platform for urea detection. Scientific Reports (2020).
4. Non-enzymatic disposable electrochemical sensors based on CuO/Co3O4@MWCNTs nanocomposite modified screen-printed electrode for the direct determination of urea. Scientific Reports (2023).
5. Processable and nanofibrous polyaniline:polystyrene-sulphonate (nano-PANI:PSS) for the fabrication of catalyst-free ammonium sensors and enzyme-coupled urea biosensors. Biosensors and Bioelectronics (2020).