Neurotransmitters: Key Players in Neurological Disorders and Advances in Their Detection

Neurotransmitters are fundamental biochemical mediators critical for maintaining homeostasis, neuronal communication, and regulating cognitive and motor functions within the central nervous system (CNS). Dysregulation in neurotransmitter systems—including dopamine, serotonin, glutamate, acetylcholine, and gamma-aminobutyric acid (GABA)—is intricately linked to a broad spectrum of neurological and neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, and others. This review synthesizes current understanding of the synthesis, localization, and functional roles of neurotransmitters in health and disease. Recent advances in detection methodologies, including electrochemical and optical biosensors, microfluidic integration, nanoscale sensors such as surface-enhanced Raman scattering (SERS), and advanced imaging techniques, have significantly enhanced sensitivity and specificity for real-time and spatial monitoring of neurotransmitter dynamics. The incorporation of nanotechnology and artificial intelligence-driven analytics further bolsters detection precision, facilitating personalized diagnostics and therapeutic monitoring. Pharmacological treatments addressing neurotransmitter imbalances—with examples including dopaminergic replacement in Parkinson's and acetylcholinesterase inhibitors in Alzheimer's—are discussed alongside emerging neuromodulation strategies such as transcranial magnetic stimulation (TMS) and deep brain stimulation (DBS). Moreover, the manuscript emphasizes the relevance of genetic and epigenetic variability influencing individual responses, underscoring the shift toward precision medicine. Future research directions prioritize the development of non-invasive, longitudinal monitoring tools, integrative multi-disciplinary collaborations, and innovative therapeutics targeting neurotransmitter signaling pathways, aiming to revolutionize the management and treatment outcomes of neurological disorders. The integration of cutting-edge detection technologies and therapeutic modalities promises to redefine clinical practice, improve patient quality of life, and advance our understanding of complex neurodegenerative disease mechanisms.