Standard Operating Procedure for Foam Sensor Calibration in Bioreactor Systems for Biosimilars
| Department | Biosimilars |
|---|---|
| SOP No. | SOP/BS/073/2025 |
| Supersedes | SOP/BS/073/2022 |
| Page No. | Page 1 of 10 |
| Issue Date | 04/05/2025 |
| Effective Date | 06/05/2025 |
| Review Date | 04/05/2026 |
1. Purpose
To establish a procedure for calibrating foam sensors installed in bioreactor systems used during upstream biosimilar production, ensuring accurate foam detection and triggering of automated antifoam addition or alarms.
2. Scope
This SOP applies to all foam sensors used in stainless steel and single-use bioreactors at scales ranging from 10L to 2000L within the biosimilars production unit.
3. Responsibilities
- Process Technicians: Perform routine calibration and function tests of foam sensors as per schedule.
- Engineering Department: Maintain calibration records and troubleshoot sensor failures.
- QA Officer: Verify compliance with calibration frequency and documentation accuracy.
4. Accountability
The Upstream Production Manager is accountable for ensuring foam sensors are calibrated and functional before batch execution.
5. Procedure
5.1 Calibration Frequency
- Foam sensors shall be calibrated:
- Before first use in a new campaign
- Every 3 months during routine operations
- After cleaning or sensor replacement
5.2 Preparation
- Obtain certified calibration standard foam or prepare test solution with 0.1% Tween 20 in water.
- Verify sensor tag number and ensure it matches batch documentation.
- Switch the bioreactor control system to manual calibration mode.
5.3 Calibration Procedure
- Install sensor in the foam calibration vessel or designated port.
- Submerge sensor tip into air to set the zero or baseline reading.
- Immerse the sensor in foam solution and confirm alarm or signal is triggered.
- Adjust sensor sensitivity if foam is not detected at predefined levels.
- Record both ‘no foam’ and ‘foam present’ voltage or signal values (Annexure-1).
5.4 Functionality Test
- Simulate foaming condition inside a bioreactor using sterile foam solution.
- Confirm sensor activation and automated antifoam pump engagement.
- Reset sensor output after test and return control system to auto mode.
5.5 Documentation
- Complete the Foam Sensor Calibration Log (Annexure-1).
- Attach printouts of system verification (if available) to the logbook.
6. Abbreviations
- SOP: Standard Operating Procedure
- QA: Quality Assurance
- mV: Millivolt (sensor signal output)
7. Documents
- Foam Sensor Calibration Log – Annexure-1
8. References
- ICH Q9 – Quality Risk Management
- WHO TRS 1010 – GMP for Biological Products
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Foam Sensor Calibration Log
| Date | Sensor ID | Baseline Reading (mV) | Foam Reading (mV) | Calibrated By | Remarks |
|---|---|---|---|---|---|
| 04/05/2025 | FS-BR-07 | 25 | 88 | Vinay Pawar | Pass |
Revision History:
| Revision Date | Revision No. | Revision Details | Reason for Revision | Approved By |
|---|---|---|---|---|
| 04/05/2025 | 2.0 | Updated foam simulation method and added calibration frequency | Annual Review |