In vivo monitoring of local pH values in a live rat brain based on the design of a specific electroactive molecule for H+

pH plays an important role in the biochemical, ion-regulatory, or electrical machinery of nerve and glial cells, and is considered to be related to a number of degenerative diseases. Herein, we first develop a two-channel electrochemical ratiometric biosensor for local pH determination in a live rat brain, and report the accurate pH values in the different regions of live brains upon global cerebral ischemia.