Advances in biosensors for diagnosis of Alzheimer's and Parkinson's diseases.

Early diagnosis by detecting ultralow concentrations of disease biomarkers is critical for timely treatment of the two most common neurodegenerative diseases, Alzheimer's and Parkinson's diseases. Innovative biosensors technologies can provide accurate, faster, and cheaper diagnostic pathways. In this review, the most recent electrochemical and optical sensing and biosensing platforms for diagnosing these diseases are critically selected and reviewed. Diagnostic targets (generally biomarkers) related to each disease and novel technologies, such as nanomaterials and biomolecular techniques to optimize the detection process and enhance signals, are discussed. In particular, multiplex detection and detection of multiple analytes by a (bio) sensing platform, to improve clinical sensitivity and selectivity are considered. This review is intended to open new approaches in the field and advance future research by identifying those strategies that optimize real-world performance and minimize present shortcomings.