Potential of Low-Frequency Raman Spectroscopy for Structural Screening of Lipid-Based Drug Delivery Systems for...

Area of Science:

• Materials Science
• Biophysics
• Physical Chemistry

Background:

• Lipid lyotropic liquid crystals (LLCs) are promising for drug delivery.
• Understanding their structural dynamics is crucial for optimizing formulations.
• Monoolein and phytantriol are key lipids with established roles in LLCs.

Purpose of the Study:

• To investigate dynamic structural changes in LLCs upon mixing lipid systems.
• To establish correlations between low-frequency Raman (LFR) spectral features and mesophase structures.
• To assess the utility of LFR in tracking composition-driven mesophase transformations and drug interactions.

Main Methods:

• Simultaneous low-frequency Raman (LFR) and small-angle X-ray scattering (SAXS) at a synchrotron facility.
• Investigation of monoolein and phytantriol systems.
• Perturbation of LLC structures using vitamin E acetate emulsion and cinnarizine (a lipophilic drug).

Main Results:

• Direct correlations were established between LFR spectral features and SAXS-determined mesophase parameters.
• LFR was shown to sensitively track composition-driven mesophase transformations.
• The concurrent LFR-SAXS approach evaluated cinnarizine's affinity and its role in forming nanostructures for enhanced drug solubilization.

Conclusions:

• Combined LFR-SAXS measurements provide valuable insights into lipid mesophase dynamics.
• LFR can serve as a structure-sensitive probe for monitoring complex lipid systems.
• This approach can inform and expand the future use of LFR in drug delivery research.