Development of Nickel Nanowire on N-doped Carbon supported for Urea Measurement in Spent Dialysate for End-Stage Renal Disease Prognosis

This study demonstrated a non-enzymatic electrochemical biosensor for urea measurement in spent dialysate as an alternative method of traditional blood-based measurement in patients with end-stage renal disease. On-site monitoring urea in dialysate is strategically cost-effective and practically robust for rapid diagnosis and treatment efficacy. Experimentally, scalable nickel (Ni) nanowire on nitrogen-doped carbon (NC) supported was synthesized and characterized morphology, elemental composition, and electrochemical performance by Field-Emission Transmission Electron Microscopy, Selected Area Energy Diffraction, X-ray Energy Dispersive Spectroscopy, and X-ray diffraction. Furthermore, electrochemical measurements were assessed by cyclic voltammetry and differential pulse voltammetry in phosphate buffer saline, simulated dialysate, and real spent dialysate from chronic kidney disease patients. Upon successive urea addition, the as-prepared Ni nanowire/NC exhibited the estimated limit of detection (LOD) of 0.408 mM and the sensitivities of 68.91 μA.cm^-2.mM^-1 (R² = 0.986) and 7.57 μA.cm^-2.mM^-1 (R² = 0.989) in the lower range (below 1 mM) and the upper range (1-20 mM), respectively in simulated dialysate. Furthermore, the urea determination in the 4 hour-treatment spent dialysate, obtained from three patients, was also carried out in comparison with the clinical standard test, demonstrating a comparable and practical onsite urea measurement in future prognosis.