Fast understanding of phases and phase separation in liquid crystal drug delivery systems using deuterium solid-state NMR

Abstract

Characterization of lipid based (SPC/GDO/H2O) liquid crystal (LC) drug delivery system is non-trivial and highly complex, especially when multiple and intermediate phases are present. The phase behavior of such mixtures during hydration or delivery is still poorly understood and therefore, characterizing these systems is crucially important towards controlling their function and enhancing the understanding of their drug release behavior. Current work has established an easy way to identify liquid crystal phases and phase mixtures using deuterium (2H) solid-state nuclear magnetic (NMR) spectroscopy under static conditions without disrupting the three dimensional structure and phases, as magic-angle spinning (MAS) could lead to disruption of the phases. Small angle X-ray scattering (SAXS) technique and optical microscopy were also employed to corroborate the study.