Seth A. Kriz, PhD Student in Chemical Engineering
Area of focus: Bioseparations, Vaccine Manufacturing
Topic: Purifying viral vaccines by two-phase aqueous extraction
Project Summary: The World Health Organization (WHO) estimates as many as 650,000 people die annually from the seasonal influenza virus. Viral vaccines are an effective tool to combat this enormous problem, but current manufacturing purification methods suffer from high costs and yields of less than 30%. A switch from batch to fully continuous processing, which is acknowledged by the FDA to increase capacity and product consistency, is necessary to meet demand. Aqueous two-phase systems (ATPS) constructed of inexpensive, environmentally-friendly polymers and salts are an ideal method to replace traditional chromatography steps that rely on costly resins and operate discontinuously. Previously, we achieved over 80% recovery of two model viral products in the polymer phase of ATPS with high host cell protein and DNA removal. However, the purified viral product is too viscous for further polishing by traditional filtration methods. Thus, a polymer removal step is required. Here we developed a second stage of ATPS to back-extract the virus from the polymer-rich primary product into a gentle salt solution ready for polishing. Preliminary results demonstrate that back-extraction completes a fully continuous viral particle extraction process using ATPS.