Glassy Carbon Electrode As a Promising Sensor for Healthcare and Environmental Monitoring

Glassy carbon electrode (GCE) has been explored in the present investigations and applied thereafter for biomedical applications and environmental monitoring. A novel electrochemical approach for the quantitative analysis of methylglyoxal as a biomarker in human plasma has been developed. An electrochemical sensor employing a single walled carbon nanotube modified GCE for the sensitive detection of methylglyoxal is delineated for the first time employing square wave voltammetry. This modified electrode exhibits potent and sustained electron-mediating behavior and a well-defined reduction peak in response to methylglyoxal was observed. The interfering effect of common coexisting metabolites in human whole blood has also been investigated. The developed assay was shown to be specific and sensitive for the analysis of plasma levels of methylglyoxal in healthy volunteer and diabetic patients.

A simple, rapid and highly selective method for the determination of the most abundant α-dicarbonyl compound in wine and beer has been developed for the first time by employing square wave voltammetry. A novel electrochemical sensor, based on the electrodeposition of platinum nanoparticles onto single wall carbon nanotubes that were casted on a GCE substrate has been developed. This modified electrode was successfully applied for the quantitative analysis of methylglyoxal in wine and beer samples. The developed sensor possesses advantageous properties such as a high active surface area, stability, and a rapid electron transfer rate, which cumulatively demonstrate high performance toward the electrocatalytic reduction and detection of methylglyoxal.

A promising direct and simultaneous electrochemical determination method of phenolic pollutants in wastewater samples was constructed successfully on GCE with advantages being rapid, simple, convenient, sensitive, in situ and inexpensive. The electrochemical characteristics of multi-component phenolic pollutants, such as phenol and 4-nitrophenol were investigated on GCE employing square wave voltammetry technique. Each of them displayed good linear relationship between their oxidation peak currents and their corresponding concentrations in a rather wide range coexisting with the other phenolic pollutant. The effect of different experimental and instrumental parameters such as solution pH and square wave frequency were examined. Square wave voltammetry was employed to investigate the electrochemical characteristic of phenol and 4-nitrophenol at GCE and successfully realize the electrochemical separation and simultaneous determination of multi-component phenols at GCE without any modification for the first time.