Recent Advances in Analytical Approaches to Determine Neurotransmitters in Biological Samples

Neurotransmitters play an important role in the human body, as regulators and messengers in cellular function, body regulation, and homeostasis, operating through the nervous system and organs.As neurotransmitters can directly affect the central nervous system, including the brain, they are thought to be directly and/or indirectly related to various neurological disorders.Therefore, to understand the pathophysiological mechanisms underlying neurological disorders, analytical methods are required for detecting neurotransmitters in biological samples.Although numerous sample preparation techniques have been introduced for neurotransmitter profiling, advanced microextraction techniques are characterized by simple and easy operation, consuming less of harmful organic solvents and wasting fewer biological samples.Chromatography and mass spectrometry are indispensable for neurotransmitter profiling.Chromatography can separate various neurotransmitters from matrix interference in complicated biological samples.Mass spectrometry combined with chromatographic separation enables sensitive and selective determination of trace levels of neurotransmitters.Furthermore, several trials have been conducted to identify neurotransmitters as potential biomarkers for neurological diseases.In this study, we review and organize recently reported articles to help readers develop analytical methods for profiling neurotransmitters and describe applications to biological samples, to provide insights into the mechanisms of neurological diseases.