Events

Stimulated Raman Scattering Microscopy: Theory and Applications in Nano Imaging

Presented By: Xin Gao

Abstract:
Stimulated Raman scattering (SRS) microscopy is a fast, label-free imaging technique widely used in biomedicine and materials science. This study introduces a unified theoretical framework to quantitatively interpret SRS microscopy. Through a phenomenologically defined stimulated Raman cross section, a strong molecular-intrinsic response is revealed. By connecting stimulated and spontaneous Raman cross sections via both heuristic and quantum mechanical approaches, this work uncovers a dual nature of Raman scattering and explains key phenomena such as signal saturation and sensitivity limits. Building on this framework, the strength of SRS microscopy is demonstrated in imaging nanoparticles at the nanoscale. Applications include solid lipid nanoparticles, poly(lactic-co-glycolic acid) (PLGA), and polystyrene nanoplastics. These experiments highlight SRS’s superior performance in capturing chemical detail with high spatial resolution, and establish a generalized bio-orthogonal imaging approach that leverages intrinsic vibrational signals for non-invasive, high-content imaging in biomedical systems.