Raman Spectroscopy Techniques for the Investigation and Diagnosis of Alzheimer's Disease

Abstract

Alzheimer's disease (AD) is the most common neurodegenerative disorder, resulting in memory loss, cognitive decline, bodily function impairment, and finally death. The growing number of people suffering from AD increasingly urges the development of effective early diagnosis and monitoring techniques. Here, we review the most recent developments in the field of Raman-based techniques, which have shown a significant potential in identifying AD by detecting specific biomarkers in biological fluids, as well as in providing fundamental insights into key molecules involved in the disease progression or in the analysis of histological specimens of patients with AD. These techniques comprise spontaneous and resonant Raman spectroscopies, exploit plasmon-or fiber-enhanced effects, such as surface-, tip-or fiber-enhanced Raman spectroscopies, or involve non-linear techniques like coherent Raman scattering. The scientific efforts employed up to now as well as the rapid technological advancements in optical detection instruments (spectrometers, lasers, substrates for analysis, etc.) and the diffusion of advanced data processing methods suggest a leading role of Raman techniques in the perspective of a preclinical or clinical detection of AD.

The Emerging Role of Raman Spectroscopy as an Omics Approach for Metabolic Profiling and Biomarker Detection toward Precision Medicine

“…Patients identified as high risk through genetic testing or those with early symptoms could therefore be recommended to have a serum metabolic analysis that would complement current clinical measures. Readers specifically interested in the utility of RS in Alzheimer’s and Parkinson’s disease are encouraged to read focused reviews on this topic. − …”

Development of a wearable surface enhanced Raman scattering sensor chip based on silver nanowires for rapid detection of urea, lactate and pH in sweat

“…Surface-enhanced Raman scattering (SERS) is a spectroscopic technique that permits the label-free detection and vibrational characterization of analytes at sub-micromolar concentrations thanks to the plasmonic amplification of the Raman optical signals generated in proximity of noble metal nanoparticles surface (hot spots) [3,4]. The possibility to easily integrate SERS-active layers onto flexible substrates, coupled with the recent availability of low-cost, miniaturized, handheld commercial Raman spectrometers, have paved the way for the development of optical technological platforms for the non-invasive healthcare monitoring by sweat inspection.…”

Development of a Wearable Sweat Sensor Chip Based on Surface-Enhanced Raman Spectroscopy

“…Surface-enhanced Raman scattering (SERS) is a spectroscopic technique that permits the label-free detection and vibrational characterization of analytes at sub-micromolar concentrations thanks to the plasmonic amplification of the Raman optical signals generated in proximity to noble metal nanoparticle surfaces (hot spots) [3,4]. The possibility of easily integrating SERS-active layers onto flexible substrates, together with the recent development and commercial availability of low-cost, miniaturized, and handheld Raman spectrometers, has paved the way for the development of optical technological platforms for non-invasive healthcare monitoring via sweat inspection.…”