Standard Operating Procedure for Sample Storage at -20°C and -70°C in BA/BE Studies
| Department | BA-BE Studies |
|---|---|
| SOP No. | SOP/BA-BE/075/2025 |
| Supersedes | SOP/BA-BE/075/2022 |
| Page No. | Page 1 of 9 |
| Issue Date | 17/04/2025 |
| Effective Date | 20/04/2025 |
| Review Date | 17/04/2026 |
1. Purpose
To define a standardized procedure for the proper storage of biological samples, including plasma, serum, and whole blood, at -20°C and -70°C in Bioavailability/Bioequivalence (BA/BE) studies, ensuring stability and traceability of samples until analysis.
2. Scope
This SOP applies to all study personnel involved in transferring, placing, monitoring, and maintaining biological samples in temperature-controlled storage units at -20°C and -70°C at the clinical site or bioanalytical lab.
3. Responsibilities
- Lab Technician: Places and retrieves samples from designated freezers, logs entries, and ensures temperature stability.
- Clinical Research Coordinator (CRC): Verifies freezer allocation and sample integrity.
- QA Officer: Reviews storage records and conducts periodic audits.
4. Accountability
The Bioanalytical Department Head is accountable for ensuring that all biological samples are stored under validated conditions and documentation is maintained for audit and regulatory purposes.
5. Procedure
5.1 Freezer Qualification and Monitoring
- Ensure that freezers are:
- Qualified and calibrated as per equipment validation protocol
- Maintained between -18°C to -22°C (for -20°C freezer)
- Maintained between -68°C to -75°C (for -70°C freezer)
- Install 24×7 temperature monitoring system with alarm notifications.
- Document daily temperatures in Annexure-1: Freezer Temperature Monitoring Log.
5.2 Sample Placement
- Verify that samples are:
- Correctly labelled with subject ID, timepoint, and aliquot number
- Pre-frozen at controlled conditions before transfer (if applicable)
- Log freezer ID, rack number, and sample code in Annexure-2: Sample Storage Log.
5.3 Storage Layout and Access
- Assign fixed racks and box positions for each study to avoid misplacement.
- Restrict access to trained lab staff and record entries in Annexure-3: Freezer Access Log.
5.4 Sample Retrieval and Transfer
- During sample transfer to bioanalytical labs:
- Log retrieval time and temperature condition
- Ensure transport containers are pre-cooled
- Update Annexure-2 and generate chain-of-custody documentation.
5.5 Backup Plan for Power Failure
- Ensure each freezer is connected to a UPS or backup generator.
- Keep dry ice and portable -70°C freezer ready for emergency transfer.
5.6 Deviation and Alarm Management
- Record any out-of-limit temperature excursions in Annexure-4: Temperature Deviation Log.
- Notify QA and PI for impact assessment and resolution.
6. Abbreviations
- BA: Bioavailability
- BE: Bioequivalence
- CRC: Clinical Research Coordinator
- QA: Quality Assurance
- ID: Identification
7. Documents
- Freezer Temperature Monitoring Log – Annexure-1
- Sample Storage Log – Annexure-2
- Freezer Access Log – Annexure-3
- Temperature Deviation Log – Annexure-4
8. References
- ICH E6(R2) – Good Clinical Practice
- US FDA Guidance on BA/BE Studies
- WHO Laboratory Biosafety Manual
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Freezer Temperature Monitoring Log
| Date | Freezer ID | Temperature (°C) | Time | Checked By | Remarks |
|---|---|---|---|---|---|
| 17/04/2025 | FZ-075 | -70.2 | 08:00 | Ravi Nair | Normal |
Annexure-2: Sample Storage Log
| Subject ID | Sample Code | Freezer ID | Rack No. | Stored By | Storage Time |
|---|---|---|---|---|---|
| VOL-075 | VOL075/P1/2h/A1 | FZ-02 | R2 | Sunita Reddy | 09:10 |
Annexure-3: Freezer Access Log
| Date | Time | Accessed By | Purpose | Freezer ID |
|---|---|---|---|---|
| 17/04/2025 | 11:00 | Nisha Verma | Sample retrieval | FZ-075 |
Annexure-4: Temperature Deviation Log
| Date | Time | Observed Temp | Duration | Cause | Action Taken | Reviewed By |
|---|---|---|---|---|---|---|
| 16/04/2025 | 03:30 | -64.5°C | 25 min | Power issue | Transferred to backup freezer | Dr. Arvind Shah |
Revision History:
| Revision Date | Revision No. | Details | Reason | Approved By |
|---|---|---|---|---|
| 12/01/2022 | 1.0 | Initial release | Process definition | QA Head |
| 17/04/2025 | 2.0 | Expanded deviation management and access logs | Audit requirement | QA Head |