Unraveling the complex electrochemistry of serotonin using engineered graphitic sensors.
Analyst
; 148(1): 105-113, 2022 Dec 20.
Article
em En
| MEDLINE
| ID: mdl-36412489
ABSTRACT
Fast-scan cyclic voltammetry (FSCV) with micron-sized carbon sensors is a promising approach for monitoring the fast dynamics of serotonin (5-HT) neuromodulatory signals in the brain. However, sensor performance using FSCV can be compromised by complex chemical reactions associated with the reduction and oxidation of 5-HT, posing considerable challenges to detection of 5-HT in vivo. Herein we describe the use of engineered graphitic sensors to characterize the complex electrochemistry of 5-HT under a wide range of measurement conditions, with the aim of optimizing the FSCV conditions for in vivo quantitative 5-HT detection. These measurements reveal that water plays a significant role in driving side reactions during low-voltage FSCV measurements, leading to the observation of a well-defined secondary redox couple we associated with the redox reaction of tryptamine 4,5-dione. Remarkably, these side reactions can persist subsequent to the primary redox events associated with 5-HT. Furthermore, the results reveal a critical deviation from this ideal redox behavior if the FSCV anodic limit exceeds +0.8 V, which can be attributed to the generation of radical species from water oxidation. These new insights could lead to new FSCV protocols for more reliable 5-HT detection.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Serotonina
/
Grafite
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article