By developing new delivery systems, we can improve the bioavailability of new active
ingredients, which are often poorly soluble. New nanodelivery systems can overcome the
limitations of already known colloidal delivery systems and enable targeted delivery, controlled
release, and improved encapsulation efficiency. In this master's thesis, we incorporated poorly
soluble model active ingredient A into nanostructured lipid carriers (NLCs) and evaluated the
observed parameters such as size, polydispersity index, zeta potential, encapsulation efficiency
and drug loading after preparation and storage.
NLCs were prepared by high-shear homogenization and contained the solid lipid Compritol 888
ATO, the stabilizers PEG 2000-DSPE and Poloxamer 188, the liquid lipid Captex 200, and
model active ingredient A. We prepared 149.17 ± 8.35 nm NLC with an encapsulation efficiency
of 80.62 ± 3.03% and drug loading of 1.96 ± 0.06%. The amount of incorporated model active
ingredient A decreased rapidly after the preparation of NLC, which prompted us to optimize the
composition and preparation process. During the optimization, we investigated (i) the influence
adding the antioxidant BHA and (ii) the effect of different storage conditions.
Because the sample underwent numerous physical and chemical changes during storage, we
removed water from the dispersion by drying it in a dryer and freeze-dryer as part of the
manufacturing optimization process. The lyophilization process was further optimized by (i)
adding different polymers, (ii) different freezing methods prior to the lyophilization process,
and (iii) using different approaches to redisperse the lyophilizates. With lyophilization, we
prepared a dry powder from the NLC dispersion, which was evaluated and stored after
redispersion. The optimized sample prepared from the NLC dispersion with the addition of
polyethylene glycol 6000 was frozen in liquid nitrogen, lyophilized and redispersed with
purified water using a vortex mixer. The optimized P6000-LTD sample had a larger NLC and
approximately 7% higher encapsulation efficiency than the initial formulation NLN25 °C. Despite
conducting numerous experiments, it is our conclusion that lyophilization is not a suitable
approach for optimizing the produced NLC. We believe it is imperative to explore alternative
approaches to enhance the stability of the NLC.
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