This master´s thesis deals with the study of the incorporation of low and high molecular weight substances into liposomal systems. The aim of the work was to determine the encapsulation efficiency (EE) of the active substance and the influence of individual components of the liposomal system on EE. Liposomes were prepared from dipalmitoylphosphatidylcholine. They were stabilized by cholesteroland and phosphatidic acid was added to give a negative charge. Stealth properties gain the binding of polyethylene glycol and other trimethyl chitosan we enabled the entry of liposomes into the bloodstream by the paracellular pathway. Vitamin C and the enzyme bromelain were used for incorporation into liposomes. UV-VIS spectrophotometry was used to determine the encapsulation efficiency of liposomes prepared by combining the individual components. It has been suggested that vitamin C and the enzyme can be incorporated into liposomes, but an enzyme with a higher EE. Furthermore, phosphatidic acid and trimethyl chitosan have been found to affect EE, which increases the EE of vitamin C and decreases the EE of the enzyme.