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Ge on Si waveguide mid-infrared absorption spectroscopy of proteins and their aggregates.

ABSTRACT: Specific proteins and their aggregates form toxic amyloid plaques and neurofibrillary tangles in the brains of people suffering from neurodegenerative diseases such as Alzheimer's and Parkinson's. It is important to study these conformational changes to identify and differentiate these diseases at an early stage so that timely medication is provided to patients. Mid-infrared spectroscopy can be used to monitor these changes by studying the line-shapes and the relative absorbances of amide bands present in proteins. This work focusses on the spectroscopy of the protein, Bovine Serum Albumin as an exemplar, and its aggregates using germanium on silicon waveguides in the 1900-1000 cm-1 (5.3-10.0 µm) spectral region.

SUBMITTER: Mittal V

PROVIDER: S-EPMC7449756 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Ge on Si waveguide mid-infrared absorption spectroscopy of proteins and their aggregates.

Mittal Vinita V Devitt George G Nedeljkovic Milos M Carpenter Lewis G LG Chong Harold M H HMH Wilkinson James S JS Mahajan Sumeet S Mashanovich Goran Z GZ

Biomedical optics express 20200728 8

Specific proteins and their aggregates form toxic amyloid plaques and neurofibrillary tangles in the brains of people suffering from neurodegenerative diseases such as Alzheimer's and Parkinson's. It is important to study these conformational changes to identify and differentiate these diseases at an early stage so that timely medication is provided to patients. Mid-infrared spectroscopy can be used to monitor these changes by studying the line-shapes and the relative absorbances of amide bands ...[more]

PMID: 32923073

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