Liquid crystalline nanoparticles combine the advantages of liquid crystals and nanocarriers. This dual nature enables the incorporation of a broad range of active pharmaceutical ingredients, as well as their targeted and sustained release. In this master’s thesis, liquid crystalline nanoparticles were prepared using two methodological preparation approaches: high-energy “top-down” techniques and low-energy “bottom-up” methods. In this master’s thesis we investigated the influence of various particle size reduction techniques, processing conditions, and component ratios on the formation and properties of the nanoparticles. The resulting samples were assessed by measuring particle size and polydispersity index, followed by visual evaluation, which guided the selection of samples for small-angle X-ray scattering analysis to confirm the presence of mesophases. Within the “top-down” approach, several particle size reduction strategies were tested. Due to the similarity among the obtained samples, we concluded that the composition of the formulation plays a more critical role in liquid crystalline nanoparticle formation than the specific processing technique. This was further corroborated by results from the “bottom-up” methods. The mesogen (glycerol monooleate) plays a central role, and its proportion in the selected lipid must be as high as possible. Among the tested lipids, only Monomuls90 proved suitable, containing 97.7% glycerol monooleate. The ratio between the lipid and the stabilizer (poloxamer 407) is also crucial to prevent particle aggregation and gel formation. In the “bottom-up” methods, ethanol was employed as a hydrotrope. The results indicated that optimal lipid-to-ethanol ratios range between 2:1 and 3:1. Samples prepared using this method also revealed a significant impact of processing temperature. None of the samples produced at 40 °C exhibited liquid crystalline nanoparticles formation, and gelation occurred more frequently. Due to the similarity among samples prepared with buffers of varying pH values, we inferred that pH alone does not notably affect liquid crystalline nanoparticles formation. On the other hand, comparative analysis of samples prepared via “top-down” methods demonstrated that the presence of electrolytes can markedly influence the formation of the desired structures. The presented findings provide a solid foundation for further optimization of liquid crystalline nanoparticles as drug delivery systems and open numerous avenues for future research in the field of advanced pharmaceutical delivery technologies.
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