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A low-frequency Raman (LFR) probe was coupled to an in-line small-angle X-ray scattering (SAXS) beamline to test the capabilities of a combinatory approach for the determination of lipid and drug behavior during the enzymatic lipolysis of milk-based oral formulations. Cinnarizine was used as the model drug, and its solubilization dynamics as well as its potential impact on the supramolecular structures formed by the digestion products of bovine milk were evaluated from the perspective of both techniques. The SAXS data were superior in distinguishing various liquid crystalline assemblies formed during the digestion process, with LFR providing complementary information regarding the formation of calcium soaps. On the other hand, studying changes in the LFR domain allowed the differentiation of drug solubilization and precipitation; processes that were less clear from the X-ray scattering data. Given the relative simplicity of the combined experimental setup, these results highlight the advantages that the combination of the two techniques can provide for understanding and developing new lipid-based formulations and will help to translate the results obtained at synchrotron facilities to routine analysis procedures in laboratory/industry-based environments.

Low-frequency Raman (LFR) spectroscopy is presented as a viable tool for studying the hydration characteristics of lyotropic liquid crystal systems herein. Monoolein was used as a model compound, and its structural changes were probed both in situ and ex situ which enabled a comparison between different hydration states. A custom-built instrumental configuration allowed the advantages of LFR spectroscopy to be utilized for dynamic hydration analysis. On the other hand, static measurements of equilibrated systems (i.e., with varied aqueous content) showcased the structural sensitivity of LFR spectroscopy. The subtle differences not intuitively observed between similar self-assembled architectures were distinguished by chemometric analysis that directly correlated with the results from small-angle X-ray scattering (SAXS), which is the current “gold standard” method for determining the structure of such materials.