Discriminating Polymorph Distributions In Pharmaceutical Tablets Using Stimulated Raman Scattering Microscopy

Stimulated Raman scattering (SRS) imaging is used to probe active pharmaceutical ingredient exhibiting polymorphism within compact tablets. We show that few SRS images performed at selected wavenumbers allow to access both active pharmaceutical ingredients polymorphs and excipients from which molecular mapping is retrieved over millimetre-size areas. We exemplified the approach using SRS images acquired at five wavenumbers to map clopidogrel and amibegron polymorphs embedded into excipients (polyethylene glycol, corn starch, and mannitol tablets). Our study demonstrates that SRS imaging can be used as a novel fast molecular mapping technique for pharmaceutical tablets characterization.