Amperometric Simultaneous Measurement of NO, CO and H2s during Induced Focal Seizures Using a Triple Microsensor

Abstract

In these days, nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) are well known as endogenous neurotransmitters in mammalian cells and have been studied regarding their mechanisms playing the roles as neurotransmitters in vivo. However, the actual relations among these three gases in transmitting neuronal signals in brain are still controversial and therefore, direct real-time concurrent analysis of NO, CO and H2S is required to clarify their biological relations.In current presentation, we demonstrate the fabrication of a NO/CO/H2S triple sensor and the simultaneous real-time measurements of these three gases at a rat brain surface under acute seizure using the sensor. This sensor consists of three platinum (Pt) disk working electrodes: 50, 76 and 50-μm diameter Pt microdisks (denoted as WE1, 2 and 3, respectively). The Pt disks of WE 2 and 3 are etched electrochemically and further electrodeposited with metal nanoparticles (Ru and Au, respectively). Then, the surface of each electrode is covered with a different intended target-selective membrane. These membranes are adapted for the selectivity to the gases excluding other biological interferences. Finally, these electrodes are applied with different optimized potentials, respectively to cause the oxidation of individual target gases and the oxidation currents are monitored. The developed NO/CO/H2S triple sensor is characterized in terms of its performances such as sensitivity, selectivity, etc. The sensors is utilized to monitor the concentration changes of NO, CO and H2S gases at a rat brain cortex under a seizure induced with administration of 4-acetamidophenol (AP). The actual patterns of the real-time concurrent changes of these gases were carefully investigated along with local field potential (LFP) signal changes. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT& Future Planning (NRF-2017R1A2A2A14001137).