An Electrochemical Biosensor with Dual Signal Outputs for Ratiometric Monitoring the Levels of H2O2 and pH in the Microdialysates from a Rat Brain

5 years ago

An Electrochemical Biosensor with Dual Signal Outputs for Ratiometric Monitoring the Levels of H2O2 and pH in the Microdialysates from a Rat Brain

Yang Tian, Shuai Li

The serious damage of ischemia to brain function has attracted extensive attention. As two of vital signal molecules, development of biosensors for monitoring of hydrogen peroxide (H2O2) and pH in vivo is significant to understand the roles of H2O2 and pH playing in rat brain followed by ischemia. Herein, a selective and accuracy ratiometric electrochemical biosensor was developed for quantifying H2O2 and pH through both current and potential outputs in a rat brain upon ischemia. Catalase (Cat) was first employed as a specific recognition element for both H2O2 and pH. Meanwhile, an inner reference molecule, ferrocene (Fc), independent of H2O2 and pH, was used as a built-in correction to improve the accuracy. The reduction peak current of Cat increased with increasing concentration of H2O2 from 1.0 to 230 μM. Meanwhile, the peak potential negatively shifted with increasing pH from 5.91 to 7.81, resulting in determination of H2O2 and pH. Thus, combined with the remarkable analytical performance of the developed biosensor and the desirable biocompatibility of carbon fibre microelectrode (CFME), a direct and reliable approach was established to monitoring H2O2 and pH in the microdialysates collected from rat brain followed by cerebral ischemia.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/elan.201700684