Preparation and characterization of glyceryl dibehenate and glyceryl monostearate -based lyotropic liquid crystal nanoparticles as carriers for hydrophobic drugs

Lyotropic liquid crystal nanoparticles (LLCNs), including lipid-based structures, are one of the crucial candidate molecules for drug delivery applications due to several advantages in terms of low toxicity, high loading capacity, and superior pharmacokinetic properties. Generally, in literature, monoglycerides such as glyceryl monostearate are preferred lipids to produce LLCNs. However, lyotropic mesophases have previously been obtained by the incorporation of diglycerides with monoglycerides. In this study, glyceryl monostearate and glyceryl dibehenate mixtures are used as lipid compartments to produce LLCNs while Pluronic F-127 (F-127) was used as the surfactant with two methods for the first time in literature. Oil in water (o/w) and film preparation-rehydration methods were used to produce LLCNs with different lipid-to-surfactant (L:S) ratios. It was shown that L3:S7 and L7:S3 ratios provide obtaining LLCNs using the film preparation-rehydration method. Curcumin, which was used as a model hydrophobic drug was incorporated in L3:S7:C1 and L7:S3:C1 ratios. The formation of lyotropic mesophases was tracked using a Polarizing Optical Microscope (POM) and Small-Angle X-ray Scattering (SAXS). The size of the formed nanoparticles (NP) was measured using Dynamic Light Scattering (DLS) and the particles with sizes less than 300 nm namely L7:S3 and L7:S3:C1 were chosen as the optimized particles for drug delivery. The incorporation of the LLCN components was studied using FT-IR and Differential Scanning Chalorimetry (DSC) methods. It was successfully demonstrated that both curcumin and F-127 are completely covered by the lipid components of the formed LLCNs, which altogether resulted in obtaining NPs with Maltese crosses and hexagonal structures.