Raman spectroscopy is based on the principle of inelastic light scattering, enabling precise analysis and identification of materials by detecting spectral characteristics of low-frequency modes such as vibrations and rotations in molecules, solids, and two-dimensional materials. This technology offers advantages including label-free detection, rich information content, and non-destructive analysis, demonstrating broad application prospects in chemistry, biology, medicine, environmental science, and other fields. However, as a higher-order light-matter interaction process, Raman scattering has an inherently tiny scattering cross-section, with signal intensity far lower than fluorescence and Rayleigh scattering.

In a paper published in eLife, University of Michigan researchers studied the dependence of photoreceptors on glutamine.

Their results indicate that maintaining the balance of amino acids in these cells is important for photoreceptor health.