Detailed Explanation of Raman Spectroscopy Technology

Raman Spectroscopy is an analytical technique based on the inelastic light scattering effect. By measuring the frequency shift (Raman shift) generated by the interaction between incident light and molecules, molecular vibration/rotation energy level information is obtained, achieving "fingerprint recognition" of the chemical structure of substances. The following introduces the core principles, technical features, application scenarios, and development trends:

I. Core principles and spectral characteristics

Scattering mechanism

When a monochromatic laser irradiates a sample, photons collide non elastically with molecules, causing a change in the frequency of the scattered light (∆∆), a phenomenon known as Raman scattering.

The intensity of the Stokes line (∆ ∆>0, energy loss) is significantly higher than that of the anti Stokes line (∆ ∆<0, energy gain), and the actual test is mainly based on the Stokes line.

Raman shift (unit: cm ⁻¹) is independent of the incident light wavelength and only depends on the molecular energy level difference, which is a key basis for substance recognition.

Complementarity with infrared spectroscopy

Raman spectroscopy is sensitive to non-polar bonds (such as C=C, S-S), which can compensate for the blind spot of infrared spectroscopy in polar bond analysis. The combination of the two can comprehensively analyze molecular structures.

II. Technological evolution and instrument composition

Breakthrough progress in technological direction

Sensitivity enhancement surface enhanced Raman scattering (SERS) technology utilizes nanostructures to amplify signals by 10 ⁶ -10 ¹⁴ times, achieving single-molecule detection

The spatial resolution confocal microscopy system can reach 0.5 μ m (532nm laser), accurately analyzing the distribution of micro area components

Intelligent analysis of deep neural network models applied to oral cancer diagnosis with an accuracy rate of 100%

Typical instrument configuration (taking Renishaw inVia Qontor as an example):

Excitation light source: 532nm/785nm laser

Detector: High sensitivity CCD, spectral resolution ≤ 1cm ⁻¹

Function: Supports rapid imaging of solid/liquid/gas samples, semi quantitative analysis of stress, crystal structure, and chemical composition distribution

III. Core application areas

Materials Science

Research on Nanomaterial Interface (such as Plasma Thermal Electron Transfer Mechanism)

Characterization of polymer crystallinity and stress distribution

Biomedical Science

Tumor edge detection (with an accuracy rate of 91% for glioblastoma)

Ultra low concentration biomolecule detection (dCERS technology sensitivity up to 1fM)

Industrial quality inspection

Identification of drug crystal structure and analysis of semiconductor defects

IV. Future development direction

Multimodal integration: Combining infrared and atomic force microscopy techniques to enhance the analytical capabilities of complex systems.

Portable device: Develop a handheld Raman spectrometer for on-site security checks and cultural relic identification.

AI driven: Optimizing spectral deconvolution algorithms through machine learning to achieve high-throughput automated analysis.

Raman spectroscopy is accelerating its penetration from basic research to clinical diagnosis, intelligent manufacturing, environmental monitoring, and other fields. Its advantages of "non-destructive and high specificity" will continue to drive interdisciplinary innovation.