Flexible cotton-AuNP thread electrode for non-enzymatic sensor of uric acid in urine

Abstract We report on the development of an electrochemical sensor platform based on modified cotton fibers for the non-enzymatic detection of uric acid (UA), an important biomarker for gout disease. To create the flexible electrode, a cotton thread was coated with carbon ink followed by the electrodeposition of AuNPs. Then, differential pulse voltammetry (DPV) was used to evaluate the sensor performances, and a linear detection range between 10 µM and 5.0 mM of uric acid was obtained. The sensor has a low detection limit of 0.12 µM, which is optimal for use in the patients suffering from gout disease which commonly experience concentrations of uric acid in urine higher than 4.46 mM. Furthermore, we found that the detection sensitivity of the platform was not affected by the presence of other physiological compounds present in human urine. The described platform has the potential for integration in a diaper hence enabling rapid detection and screening for gout disease.