On-line backpressure sensing
CellTank and CellReactor bioreactor products facilitates a straight forward method to measure app bio mass in the scaffold.
Pressure measurement instrumentation
Increasing and successful cell expansion will eventually reach the equilibrium of high density bio mass. In order to control and maintain the desired flux through the matrix the operator is able to avoid excessive pressure drop over the matrix by reading the pressure drop in millimetre WC (water column). Range 0-500 mm WC.
The operator will use several methods in order to limit excessive cell expansion such as reduce the media temperature, change of media composition, impeller rpm rapid change for cell extraction to the reservoir for bleeding, etc.
Photo - the SS rod supports the silicone hose extending from the cover centre port to the blue OD25 mm sterile filter at the top. Two white OD50 mm sterile filters also visible. You will easily see the liquid level inside the straight vertical tube.
Precautions around pressure measurements
Insure the hose is stretched on the SS supporting rod before adding media. Insure the hose clamp is locked when adding media to the SUB and starting up the re-circulation pump to avoid liquid to reach the OD25 mm sterile filter.
When app 500 mm WC backpressure at 2 l/min flow and app 600 rpm is reached the scaffold/ matrix is filled ~50% with cells equivalent to ~1.20x10E+8 cell/ml matrix or 1.8x10E+10 in total inside the matrix. This figure measured with the bio mass sensor is ranging 80 pF. It is not recommended to exceed this figure!