Simultaneous detection of glutathione, threonine, and glycine at electrodeposited RuHCF/rGO-modified electrode

Ruthenium hexacyanoferrate/reduced graphene oxide (RuHCF/rGO) electrode was fabricated by electrochemical deposition of RuHCF on a rGO-modified electrode. Electrocatalytic oxidation and determination of glutathione, threonine, and glycine were carried out simultaneously using the modified electrode. The electrochemical sensor showed a wide linear response in the concentration range of 5.12-25.58 mu M for glutathione, 1.98-15.86 mu M for threonine, and 1.25-7.49 mu M for glycine. The RuHCF/rGO-modified electrode showed minimal interference in the presence of related compounds. The limit of detection observed for glutathione, threonine, and glycine was 1.70, 0.66, and 0.4 mu M respectively. Saliva samples were used for checking the analytical utility of the RuHCF/rGO-modified electrode for sensing the three analytes, and the recovery percentages were between 95.80 and 98.03. The electrode also exhibited long-term stability and shelf life.