Abstract:

A review. Recently, self-assembled lyotropic liq. crystals (LLCs) of lipids and water have attracted the attention of both scientific and applied research communities, due to their remarkable structural complexity and practical potential in diverse applications. The phase behavior of mixts. of glycerol monooleate (monoolein, GMO) was particularly well studied due to the potential utilization of these systems in drug delivery systems, food products, and encapsulation and crystn. of proteins. Among the studied lyotropic mesophases, reverse hexagonal LLC (HII) of monoolein/water were not widely subjected to practical applications since these were stable only at elevated temps. Lately, we obtained stable HII mesophases at room temp. by incorporating triacylglycerol (TAG) mols. into the GMO/water mixts. and explored the phys. properties of these structures. The present feature article summarizes recent systematic efforts in our lab. to utilize the HII mesophases for solubilization, and potential release and crystn. of biomacromols. Such a concept was demonstrated in the case of two therapeutic peptides-cyclosporin A (CSA) and desmopressin, as well as RALA peptide, which is a model skin penetration enhancer, and eventually a larger macromol.-lysozyme (LSZ). In the course of the study we tried to elucidate relationships between the different levels of organization of LLCs (from the microstructural level, through mesoscale, to macroscopic level) and find feasible correlations between them. Since the structural properties of the mesophase systems are a key factor in drug release applications, we investigated the effects of these guest mols. on their conformations and the way these mols. partition within the domains of the mesophases. The examd. HII mesophases exhibited great potential as transdermal delivery vehicles for bioactive peptides, enabling tuning the release properties according to their chem. compn. and phys. properties. Furthermore, we showed a promising opportunity for crystn. of CSA and LSZ in single crystal form as model biomacromols. for crystallog. structure detn. The main outcomes of our research demonstrated that control of the phys. properties of hexagonal LLC on different length scales is key for rational design of these systems as delivery vehicles and crystn. medium for biomacromols. [on SciFinder(R)]