ABSTRACT
This chapter aims to assess the possibilities and limitations of several techniques which can be applied to achieve sterility. Production of liposomes under aseptic conditions is possible, but complex and expensive. Methods for sterilizing liposomes should be destructive for microorganisms and should not affect the liposome dispersion. Autoclaving is a sterilization process based on an established time–temperature combination and is carried out in a chamber filled with saturated steam under pressure. Sterilization of liposomes in a 10-mM phosphate-saline buffer was performed by E. Mentrup et al. The stability of liposomes under the chosen conditions depended both on the chosen time, temperature, and pressure conditions, and on the characteristics of the liposomes used. γ-Irradiation becomes more and more accepted as a sterilization method of pharmaceuticals. Filtration is widely used to minimize the content of microorganisms in dispersions with small liposomes. Sterility cannot be guaranteed by testing of the final product, but is assured by validated well-defined procedures.
