A Flow-Through Chromatographic Strategy for Hepatitis C Virus-Like Particles Purification

Biopharmaceuticals are currently becoming one of the fastest growing segments of the global pharmaceutical industry, being used in practically all branches of medicine from disease treatment to prevention. Virus-like particles (VLP) hold tremendous potential as a vaccine candidate due to their anticipated immunogenicity and safety profile when compared to inactivated or live attenuated viral vaccines. Nevertheless, there are several challenges yet to be solved in the development and manufacturing of these products, which ultimately can increase time to market. Suchlike virus-based products, the development of a platform approach is often hindered due to diversity and inherent variability of physicochemical properties of the product. In the present work, a flow-through chromatographic purification strategy for hepatitis C VLP expressed using the baculovirus-insect cell expression system was developed. The impact of operational parameters, such as residence time and ionic strength were studied using scaled-down models and their influence on the purification performance was described. The flow-through strategy herein reported made use of radial-flow chromatography columns packed with an anion exchanger and was compared with a bind and elute approach using the same chromatography media. Overall, by selecting the optimal operational setpoints, we were able to achieve higher VLP recoveries in the flow-through process (66% versus 37%) with higher removal of DNA, baculovirus and host-cell protein (92%, 99% and 50% respectively).

Desaltation of the Polysaccharide of Nostoc Flagelliforme with Radial Flow Chromatography

.The process for the desaltation of the polysaccharide from the mixotrophic liquid culture of Nostoc flagelliforme with radial flow chromatography (RFC) column packed with Sephadex G-100 gel was investigated. The RFC column having 7.7 cm of bed length and 229.6 cm3 of bed volume was used in this study. The effects of some operating factors such as the sampling weight, the flow rate of eluent on the desaltation efficiency were examined. It was found that the separation efficiency increases with the decrease of sampling weight and flow rate of eluent. With 2.4 mg of sampling weight and 0.3 ml/min of flow rate of eluent, the salt content of polysaccharide was lowered from 90.42% to 2.36%. As a conclusion, this technique can be used to get rid of the eluant in the polysaccharide introduced by the ion exchange process.