Continuous purification of an enveloped and non-enveloped viral particle using an aqueous two-phase system

Meeting the increasing demand for vaccines throughout the world is key to decrease the spread of infectious diseases. The switch to a fully continuous vaccine manufacturing process would increase productivity and the supply of crucial vaccines. To aid in this switch, we have developed a novel, continuous downstream purification technique based on an aqueous two-phase system (ATPS). The system has the potential to be used as a platform system for viral product purification. A 12 kDa poly(ethylene glycol) (PEG) and trisodium citrate ATPS was able to purify porcine parvovirus (PPV) and human immunodeficiency virus type-1 group antigen virus-like particles (HIV VLPs) from cell supernatant. PPV was recovered in the PEG-rich phase at 90 ± 16% with a DNA removal of 96 ± 3% and ≥89% protein removal. The system was also able to recover 99 ± 2% of HIV VLPs in the PEG-rich phase with a 73 ± 1% DNA removal and high protein removal shown by SDS-PAGE. Continuous ATPS recovered virus at the same amount as batch recovery. This demonstrates that continuous ATPS can be scaled up and runrun continuously without a loss in purity or recovery. Mixing and settling time both played an important role in developing a continuous ATPS for viral particles