Liposomes are small spherical vesicles which are composed of lipids. Due to containing the same composition as cell walls, they are biodegradable. They can provide the opportunity for developing passively targeted therapies, and if certain ligands are bound to their wall, they are also capable of active targeting. Due to their usefulness and advantages, there are already many liposomal formulations on the market for various treatments, including cancer. With the aim of preparing the liposomes for delivering novel drugs, we have developed our own protocol to do so. Since precise protocols for a particular formulation are not available, we first chose and then optimized the protocol for the preparation of the appropriate liposomes, which would allow sufficient encapsulation efficiency of the water-soluble molecules. For the optimisation we had to vary the lipid film formation parameters, the temperature of the hydration solution and hydration techniques, optimize the composition of the hydration solution and adapt it to biological conditions and optimize the dialysis. Thus, from the initial approximately 0.1 % encapsulation, we improved the efficiency to as much as 10 % encapsulation of the model fluorescein. Vitamin C was encapsulated as a model water-soluble substance and then we tested the protocol for encapsulation of the lipophilic digoxin. The effect of both formulations on survival was verified on the MDA-MD-231 cancer line. In liposomal vitamin C, we failed to achieve an affect on cell viability and cell growth, and in liposomal digoxin its effect on cell viability was very strong, with less than 10 % of cells surviving.
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