We focused on a rapid method for the assay of protein unbound indoxyl sulfate (IS) in urine
samples by square-wave voltammetry. A sensor based on the electroactivity of commercial graphene
screen-printed electrode (GR-SPE) for sensitive estimation of uremic toxin indoxyl sulfate was presented.
The behaviors of uremic solute indoxyl sulfate on GR-SP electrodes were explored by cyclic
and square-wave voltammetry. The outcomes displayed that the GR-SP electrode exposed perfect
electroactivity to uremic toxin indoxyl sulfate and the oxidation of uremic solute IS is a multi-step and
irreversible process. The process is pH dependent and takes place with the forging of a main oxidation
product that is adsorbed on the GR-SP electrode surface. The calibration curve was achieved in the IS
concentration range of 0.5–80 µM and the limit of detection was calculated to be 0.064 µM at a signal-to-noise ratio of 3.
The use of the commercially disposable GR-SPE in human serum and urine sample assays obtained satisfactory results,
which made it a promising alternative in routine sensing applications.
Keywords: Biomolecule, electrochemical sensing, indoxyl sulfate, serum, uremic toxin, urine analysis.
Rights & PermissionsPrintExport