Wearable neural biosensors for early detection of neurodegenerative diseases

Neurodegenerative diseases, which include Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis, represent a growing worldwide health burden that can be attributed to the ageing of the population and the lack of effective modalities of early diagnosis. Conventional diagnostic methods rely on clinical assessment and neuroimaging, but they often reveal neuropathology only after it is too late, when neuronal damage has already occurred. Wearable neural biosensors are an emerging approach for continuous, non-invasive monitoring of neurophysiological, neuromuscular, and biochemical biomarkers in real-world applications. This systematic review examines of advancements in wearable biosensor design, the utilization of functional nanomaterials (graphene, CNTs, MXenes, hydrogels), signal detection modalities, and the integration of these sensors with wireless communication systems and artificial intelligence algorithms to extract clinically useful information. This review highlights applications of biosensors in the key neurodegenerative diseases, with a focus on the disease-specific biomarkers in combination with electrophysiological and motion-based signals. Challenges such as biocompatibility, long-term stability in biological fluids, data privacy, multimodal signal fusion, preclinical validation, clinical trials, regulatory systems, and ethical concerns are critically considered. The future opportunities of the multi-omics integration, personalized neuro-monitoring, and privacy-sensitive data systems are described. Overall, wearable neural biosensors show significant potential to enable earlier diagnosis and precision-based treatment of neurodegenerative disorders.