Measurement of biomolecules in the brain and neurotransmitters released from cells using electrochemical sensing systems

Abstract

Electrochemical sensing systems for measuring the concentrations of biomolecules in the brain and neurotransmitters released from cells are reviewed. It is very important to continuously monitor the changes in the biomolecule concentrations in the brain. Many micro-sensing devices have been studied to clarify physiological phenomena in biological systems. The sensitivity, selectivity, and temporal/spatial resolution of these systems must be high. Both microelectrode sensors and on-line sensors are suitable for continuous monitoring; the former can be inserted into the brain or near cells, and the latter can be easily combined with a microdialysis probe, separator, or reactor. In recent years, many researchers have been studying microfabricated chips integrated with channels, separators, detectors and so on. Such chips are called Micro Total Analysis Systems (μ-TAS); it is a new concept concerning biosensing devices. Electrochemical measurement method and neurotransmitters are summarized and application of three types of sensing system to in vivo and in vitro monitoring are discussed.