Single–Use Bioreactors Single–Use Reactors: A Panacea for Future
In today’s world of fierce competition and tough regulatory compliance pressure, to remain competitive with hassle-free production, every biopharmaceutical manufacturer is looking at some key catalysts of process change – such as modularisation, flexibility, fast changeover and minimising contamination risks. Thus, technologies engrossing this paradigm shift are coming into the forefront. Rapid advancement in disposable technologies will soon make them indispensable.
The number and variety of single-use systems available on the market for biopharmaceutical R&D and production applications has increased steadily over the past ten years. The annual growth rate reached 35 per cent in 2009, mainly due to demand for products used in upstream processing. Most single-use or disposable technologies are based on parts, which are made of plastic and are not intended for re-use
Single–Use – Multiple Options
Users today can choose from a large selection of products provided by a whole range of suppliers. Most single-use products are found in processes where protein-based biotherapeutics made from mammalian cells are the target products.
With the broad spectrum of components, sensors and single-use pumps which are available, complete single-use upstream processing for culture volumes up to 2m3 is now feasible. The range of options includes bioreactors, which use wave motion to mix materials (GE Healthcare’s Wave Bioreactor and Biostat CultiBag RM from Sartorius Stedim Biotech) as well as single-use stirred bioreactors available in a variety of versions (e.g. rigid plastic tanks from Mobius CellReady, UniVessel SU and CelliGEN BLU and flexible bag systems from S.U.B., Biostat CultiBag STR and XDR Bioreactor).
Ready to Use Biotechnology Platforms
The size, the underlying principle of operation and mixing as well as the instrumentation vary on these systems, and they all have their own defined fluid dynamics. For repetitive steps (mixing, storage, material handling, inoculant production, fermentation and biomass separation), basic operation sets have been consolidated into process platforms. These platforms are technical implementations, which combine a well-defined sequence of processes or process steps. A number of these platforms are now available for media production, fermentation and biomass separation. The size of the systems as well as the number and sequence of process steps vary.
Technical Limitations for Single–Use Technologies
There are technical limitations to the deployment of single-use technologies in upstream processing due to the plastics that are contained in the products. The list of limitations includes stability, applications spectrum, scale-up and handling.
The current size limits from the user perspective are in the 1,000-2,000 litre range for bag volumes and 30 inches for filter cartridges, even if suppliers offer larger bag systems (up to 5,000 litres). Above these thresholds, users currently install multiple systems in parallel – when they need to increase the capacity. Recent surveys by Aspen Brook Consulting indicate that 80 per cent of users regard this approach as adequate.