Enhancing Lysozyme Loading in Powderized Liposomes by Controlling Encapsulation Processes

Liposomes have demonstrated great potentials as protein carriers in various pharmaceutical applications. However, low loading amount of proteins in liposomes have been a major challenge for maximizing the therapeutics potential of the proteins. We thus aimed to enhance the loading amount of a model protein, lysozyme, in liposomes by controlling key experimental variables of a reverse phase evaporation method. The loading amount of lysozyme in liposomes was evaluated with changing type of organic solvents used, weight ratio of lysozyme/phosphatidylcholine, and volume ratio of aqueous to organic phase along with particle characterization before and after freeze-drying procedure. As a result, the loading amount of lysozyme in liposomes was considerably enhanced and the physical stability of the liposomes was maintained without any significant changes in the particle characteristics for 7 days. The findings of this study would be useful for highly efficient loading of protein therapeutics in liposomes, leading to improved therapeutic effects of the drugs.