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Hyper-Raman spectroscopy of biomolecules
Christopher B Marble1, Kassie S Marble1, Ethan B Keene2,3
1Texas A&M University, Department of Physics and Astronomy, 4242 TAMU, College Station, TX 77843, USA. yakovlev@tamu.edu.
The Analyst
|December 12, 2023
Summary
Hyper-Raman scattering (HRS) reveals vibrational modes of biomolecules. This technique, complementary to Raman scattering, offers new possibilities for molecular analysis and imaging.
Area of Science:
- Spectroscopy
- Biochemistry
- Physical Chemistry
Background:
- Hyper-Raman scattering (HRS) provides complementary vibrational information to Raman scattering.
- Biologically significant molecules often exhibit unique spectral fingerprints.
- Understanding molecular vibrations is crucial for chemical analysis and diagnostics.
Purpose of the Study:
- To report and analyze the hyper-Raman scattering (HRS) spectra of biologically significant molecules.
- To compare HRS spectra with Raman scattering (RS) and infrared absorption spectra.
- To establish a spectral data repository for biomolecules and common solvents.
Main Methods:
- Utilized a picosecond laser (532 nm, MHz repetition rate) for HRS measurements.
- Employed a commercial spectrometer and CCD detector for high signal-to-noise spectra acquisition.
- Collected spectra without resonant, nanoparticle, or surface enhancement.
Main Results:
- Acquired and analyzed HRS spectra for D-glucose, L-alanine, L-arabinose, and L-tartaric acid in aqueous solutions.
- Observed IR-active vibrational modes in HRS spectra with distinct peak intensities compared to RS.
- Compiled a spectral database including biomolecules and solvents (water, DMSO, methanol, ethanol).
Conclusions:
- HRS successfully detects IR-active vibrational modes, offering complementary information to RS.
- The spectral database supports theoretical HRS descriptions and development of dual-detection microscopes.
- Future dual-detection RS-HRS microscopes will enable simultaneous high-spatial-resolution vibrational spectroscopy.
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