Work

Ultrasensitive microelectrode with enhanced surface area for clinical glutathione sensing and quantification

Year: 2025

Type: article

Abstract: Glutathione, as an antioxidant, regulates oxidative stress in the human body. It is also an important biomarker of Alzheimer's and Parkinson's diseases. An ultrasensitive graphene oxide-silica-silver nanoparticles modified carbon fiber electrode was designed to detect reduced glutathione. The carbon fiber was dip-coated with GO-SiO 2 -AgNPs and inserted in the capillary. The fabrication was performed with the assistance of a handheld lens and under a microscope. The carbon fiber was connected to an external circuit through an electrolyte solution filled in a capillary tube and used as the working electrode. A linear correlation coefficient was obtained at optimized conditions from 0.25 μM to 3 μM versus Ag/AgCl. LoD and LoQ were 0.17μΜ±0.087 and 0.57μΜ±0.087, respectively. The proposed electrochemical sensor was successfully used for in vivo monitoring of glutathione. The sensor was compared with liquid chromatography- UV detection (HPLC-UV). The applicability of the sensor was successfully determined in in-vivo using a mouse. The developed sensor is fast, reproducible, and reliable. It is applicable for clinical diagnosis and monitoring of oxidative stress in real samples. • Graphene oxide –silica–Ag nanohybrid enhances carbon fiber electrode performance. • The increased surface area and catalytic activity allow for a rapid electrochemical process. • The sensor detected glutathione with extreme sensitivity in the 5–35 μM range. • The proposed sensor provides a promising tool for real-sample oxidative stress and clinical diagnostics.

Source: Sensors and Actuators A Physical

DOI: 10.1016/j.sna.2025.117304