Advances in Fiber Optic Biosensing Technologies for Detection of Neurological Biomarkers: A Narrative Review

Fiber optic biosensors (FOBs) have gained attention as powerful tools for detecting neuromarkers due to their high sensitivity, rapid response, and ability to be used in complex biological environments. These sensors utilize techniques such as surface plasmon resonance (SPR) and fluorescence spectroscopy, enabling the identification of biomolecules at low concentrations. Neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and multiple sclerosis (MS) pose significant health problems due to their progressive nature and the need for early detection. Biomarkers such as amyloid beta (Aβ), tau protein, α-synuclein, and neurofilament light chain (NFL) play a crucial role in the diagnosis and monitoring of these diseases. Fiber optic sensors have enhanced their accuracy and efficiency by integrating technologies, such as nanomaterials, hydrogels, and machine learning; particularly, the use of graphene and plasmonic nanostructures has improved detection sensitivity and enabled simultaneous monitoring of multiple biomarkers. Additionally, the development of implantable and wearable sensors has made long-term and noninvasive monitoring possible. Despite significant advancements, limitations such as biocompatibility, standardization of diagnostic methods, and scalability for widespread use in clinical settings remain. However, the combination of FOBs with artificial intelligence and microfluidics has opened new horizons for personalized medicine and the management of neurological diseases. These technologies have the potential to become key tools in the early diagnosis and effective monitoring of neurodegenerative diseases. This narrative review synthesizes recent advancements in FOB technology for neurological biomarker detection, highlighting interdisciplinary innovations and future clinical translation pathways.