21
Instruction Manual
6.1.1 Initialization
The user defines the batch ID and selects batch parameters by entering user-defined values and scanning consumables to populate
applicable setpoints. Pumps may be calibrated prior to or during Initialization, and the pressure sensor is zeroed out prior to introducing
liquids, and starting pumps or gas flows. Process and Batch Data files, and the Batch Timer are started when the user confirms the Batch ID.
6.1.2 Media Fill and Prime Phase
The media bottle is aseptically connected to the MCV and media is transferred by the media pump. Once media fills the MCV, the user
verifies the media volume and manually adjusts, if necessary. The recirculation pump begins priming the bioreactor until the prime
volume is reached. This step can be used to purge air from the bioreactor. Table 6-2 shows the phase setpoints.
Table 6-2.
Media fill and prime setpoints.
Setpoints
Media Flow
Media Fill Volume
Recirculation Pump Flow
6.1.3 Media Conditioning Phase
The media temperature, DO, and pH need to be stable to perform sensor calibrations. DO and pH stabilization are achieved by controlling
the agitator, air, O
2
, CO
2
, and the recirculation pump. This phase maintains the Media Phase setpoints shown in Table 6-3. Temperatures
are automatically controlled to user-setpoints. The Stabilization duration allows sufficient time to reach steady state prior to calibrating
sensors (typically 2 to 4 hours or more).
Table 6-3.
Media conditioning setpoints.
Setpoints
Agitator
Recirculation Pump
MCV Temperature
FBR Temperature
Air MFC Flow Rate
O
2
MFC Flow Rate
CO
2
MFC Flow Rate
Stabilization Duration
6.1.3.1 Sensor Calibration
Sensor Calibration is not a phase but a prompted action as part of the Media Conditioning Phase. Section 8.2.3.1 shows how to
perform calibration.
Once the system has stabilized (i.e., DO and pH signals are no longer drifting, and temperatures have reached setpoints) the sensors
can be calibrated. The system is expected to stabilize at least 2 hours after wetting the in-line sensors. Table 6-4 shows which setpoints
are controlled.
NOTE:
Temperature sensor offsets are from the nominal value. These are required as ambient conditions have been found to bias the
temperature measurements (as determined by offline experiments during setup).
Table 6-4. Probe calibration setpoints.
Setpoints
MCV DO Span Value (typically 100%)
FBR DO Span Value (typically 100%)
pH Ref Value (based on offline measurement)
MCV Temperature Offset (default is set to 3°C)
FBR Temperature Offset (default is set to 0.5°C)
