One-step Nonenzymatic Electrochemical Sensor for the Detection of Sarcosine Using Nanozyme Glutathione Copper Complex

Abstract

Background: The present study aims to develop the use of glutathione copper complex for the detection of sarcosine, a marker for prostate cancer. The glutathione-copper complex was successfully synthesized at room temperature and characterized using FTIR, UV, and Scanning Electron Micrograph. Methods: The structure of the glutathione copper complex was found to be a 1:2 Metal: Ligand ratio. The cyclic voltammogram for the glutathione-copper complex modified electrode showed an oxidation peak around -0.037 V, which indicates the irreversible oxidation of copper ions. The addition of sarcosine decreased the oxidation potential of the glutathione copper complex indicating the ability of the working electrode, for the detection of sarcosine in the sample using differential pulse voltammetry. Results: The results indicated that the glutathione-copper complex modified electrode revealed good sensitivity, selectivity, and linearity against the detection of sarcosine in the range from 0.1 μM to 2.5 μM. The LOD and LOQ were calculated using a linear prediction model, the data obtained from differential pulse voltammetry technique for known and simulated urine samples was 0.72 μM, 5.13 μM, and 1.45 μM, 39.94 μM, respectively. The sensitivity for the developed working electrode obtained for the known and simulated sample was 0.0567 μA/μM and 0.02913 μA/μM, respectively. Conclusion: Thus, we concluded that the glutathione copper complex decorated glassy carbon electrode is a good candidate for the detection of sarcosine with good selectivity and sensitivity for real-time monitoring.