Liposomes produced in a pilot scale: production, purification and efficiency aspects.

Intensive efforts have been made to establish a novel, scalable liposomal preparation technique suitable for the entrapment of even large proteins into liposomes. We have developed a new technique based on the principles of the ethanol injection technique. Herein, the principal item is the crossflow injection module, specifically designed for this purpose. This unit has the benefit of defined and characterized injection streams and permits liposome manufacture regardless of production scale, as scale is determined only by the free disposable vessel volumes. Previous publications demonstrated that the crossflow injection technique that we have developed meets all of the above-mentioned requirements. The present paper describes the entire three-step production process, consisting of encapsulation, separation of non-entrapped protein by continuous crossflow filtration, and retrieval of rh-Cu/Zn-SOD by additional filtration. Results of consecutive lots were compared, based on well-defined quality criteria.