Raman microscopy


Raman microscopy is an investigational technique for the identification of individual (sub)visible particles dispersed in a liquid formulation.

During Raman microscopy, the liquid sample is placed in a sample holder where microscopic images of the suspended particles can be taken for morphological analysis. A particle of interest is subsequently illuminated with a laser beam and the electromagnetic radiation from the illuminated particle is collected with a lens. The wavelength corresponding to that of the laser line (Rayleigh scattering) is filtered out, while the rest of the collected light is dispersed onto a detector. The recorded Raman scattering information serves as a chemical fingerprint, which is compared to a library for determination of the identity or origin of the particle.

Raman microscopy has a high spatial resolution and can be applied to particles as small as 5 µm. Depending on the particle properties, long acquisition times might be required, typically allowing for only a few particles per sample to be analyzed. Data from Raman microscopy can be combined with results obtained by flow imaging microscopy [FIM]. Hereby, the particle morphology information from both instruments is used to link particle identity to quantitative information.

Raman microscopy is typically used as a research tool during trouble-shooting and root-cause analysis.

Contact us

Need more information? Contact our experts with your questions today.