Living cells are increasingly being used in modern therapy methods such as blood transfusions, stem cell therapies and bone marrow transplantations, or in the regeneration of severe burns. The standard cultivation of these cells in open systems is associated with a high contamination risk, which can only be reduced with sophisticated equipment and correspondingly high costs and a suitable laboratory infrastructure. Using closed bag systems as a cultivation vessel can provide relief.
Common polymers usually do not provide a suitable surface for cultivation, since the cells cannot adhere. To gain adherence, the surface has to be pre-treated or coated. Therefore, a special process based on an atmospheric pressure plasma technique was developed at Fraunhofer IST which enables an automatized coating in the interior of closed plastic bags. In order to achieve coating of the interior surfaces of the bag the latter is filled with a process gas containing a gaseous film-forming agent (”precursor”). On application of a voltage to two electrodes placed above and below the bag, the plasma is ignited inside. The treatment is finished after only a few seconds and the bag can be used directly in cell cultivating after removal of the process gas. The coatings of Fraunhofer IST can be tailored for the cultivation of different human and animal cell lines as well as for human mesenchymal stem cells.
The precursor choice influences the surface properties obtained by the plasma treatment. It is possible to generate surfaces with chemically reactive groups such as primary amino groups, carboxyl groups, carbonyl groups or epoxides as well as surfaces with a defined wettability (hydrophilic, hydrophobic).
- Inside coating of closed polymer bags without sterility loss
- Homogenous coatings on the interior surfaces of the bag
- Solvent free coatings
- Short process times
- Modification of commerical systems is possible
- Wettability control for plastic surfaces (hydrophilic, hydrophobic)
- Generation of chemically reactive functional groups
- Coatings for an adherent cell cultivation in closed systems
- Surface analytics
- Process and plant development