Millie Ullah Ph.D
The BIOSTAT® CultiBag RM, a new line of disposable bioreactors recently launched by Sartorius, utilizes rocking motion mixing technology. With superior engineered control systems, process control is now available in the disposable market. The feedback control loops using disposable sensors bring new levels of confidence to process development, cell densities and product yields - traditionally unmanageable without pH and pO2 control in this type of system - are possible. Traditional reusable sensors require aseptic connection and/or insertion into the culture bag. The disposable sensors are pre-calibrated and pre-sterilized in the bag. This eliminates the need for sterilization, and cleaning, reducing validation. The reduced handling helps ensure consistent sterile operation from batch to batch.
Disposable pH and pO2 sensors replace the traditional labor intensive polarographic and galvanic sensors. An optical fiber connects to the patch through a sterile barrier - with no break in bag integrity, thereby maintaining sterility at all times. Calibration is simple and hassle free. The BIOSTAT® CultiBag RM consists of a high-quality rocker, which can be used on the bench top or in an incubator. It can also be upgraded for use with controllers for various levels of process control in batch, fed-batch and perfusion modes.
The controllers have easy-to-use, intuitive touch-screen operation, with built-in trend display for real time process monitoring. Feedback control for pH control is freely selectable for acid/CO2 and base as required. pO2 also can be controlled by a four level cascade system, freely selectable by the user. This includes nitrogen to reduce pO2 after inoculation to reduce lag times often occurring in cell culture processes. A pressure relief valve is built-in to provide added confidence in cell cultivation and bag seal integrity.
The gentle rocking motion is typically used for cell culture, Baculovirus, plant cells etc. and propagation of seeds for manufacturing processes. Cultivation of any shear sensitive cells is possible. The system is suitable for any disposable applications. Even microbial cells have been cultivated in these systems. Scale up is possible from 0.15L to 300L of culture volume, which can be transferred to either traditional stainless steel bioreactors or disposable stirred tank systems - also soon to be launched by Sartorius.