Chapter 13: Molecular Probes for the Diagnosis of Alzheimer's Disease with Implications for Multiplexed and Multimodal Strategies Check Access

Alzheimer's disease (AD) was described more than a century ago but still there are no reliable tools and methods for accurate and early diagnosis. There have been numerous efforts by the research community for the development of molecular tools to facilitate the diagnosis of AD. Fluorescent probes are well-explored molecular tools for detection and imaging of aggregation species of amyloid beta (Aβ) peptide and tau, the National Institute on Aging and Alzheimer's Association (NIA-AA) 2018 framework designated biomarkers. Positron emission tomography (PET) and magnetic resonance imaging (MRI) have emerged as techniques with the potential for clinical diagnosis of AD. A recent mass spectrometry (MS) based technique study has shown the potential and sensitivity for the accurate detection of fluid biomarkers. Apart from Aβ and tau, there exists an array of biomarkers with direct (core) or indirect role in AD and their inclusion is crucial to enhance the accuracy, sensitivity, reproducibility, and reliability of diagnosis through a multiplexed and multimodal approach. In this chapter, we provide a critical discussion on the design, various properties, functions, advantages, and disadvantages of various molecular tools and techniques developed for the diagnosis of AD, besides providing current and future outlook. Further, we describe the array of core and indirect biomarkers and propose multiplexed and multimodal detection and imaging in the brain and biofluids to deduce characteristic fingerprints that distinguish between Alzheimer's patients and healthy individuals with high precision.