Temperature profiles of beta-amyloid and tau protein using Raman spectroscopy

The rapid aggregation of misfolded proteins leads to various neurodegenerative diseases. Beta-amyloid and tau protein are two proteins associated with Alzheimer's disease. Studies have shown that Raman spectroscopy can reveal important information about protein structures, including misfolding or denaturing processes. Using a Raman microscope with an excitation laser at 532 nm, we studied the vibrational spectrum of different protein aggregations among various stages of fibrillations as a function of temperature, from 20°C to 200°C. Our results show changes in the proteins’ Raman signatures as part of the heating process. Our study demonstrates a label-free and non-destructive technique to investigate amyloid fibril formation and study their secondary and tertiary structure as a function of temperature.  Such data could, one day, enable the design of novel photothermal treatments for Alzheimer's disease.