Standard Operating Procedure for Moisture Control During Granule Drying
| Department | Tablet |
|---|---|
| SOP No. | SOP/TAB/025/2025 |
| Supersedes | SOP/TAB/025/2022 |
| Page No. | Page 1 of 7 |
| Issue Date | 13/06/2025 |
| Effective Date | 18/06/2025 |
| Review Date | 13/06/2026 |
1. Purpose
This SOP outlines the procedures for controlling moisture levels during the granule drying process, ensuring that the granules achieve the desired moisture content, which is critical for the consistency and quality of the final tablet product.
2. Scope
This SOP applies to the drying of granules in tablet manufacturing, covering the drying methods, equipment setup, and monitoring of moisture levels to prevent over-drying or under-drying of granules.
3. Responsibilities
- Granulation Personnel: Responsible for operating the drying equipment, ensuring the correct drying parameters are followed, and monitoring moisture levels during the drying process.
- Quality Control (QC): Monitors and tests the moisture content of the granules at various intervals to ensure they meet the specified moisture range.
- Quality Assurance (QA): Ensures that the granule drying process adheres to this SOP and verifies that all documentation is properly maintained and reviewed.
4. Accountability
The Production Manager is accountable for ensuring the drying process is conducted as per this SOP. The QA Manager is responsible for reviewing the drying process parameters and ensuring compliance with regulatory standards.
5. Procedure
5.1 Pre-Drying Preparation
- Ensure that the fluidized bed dryer or tray dryer is clean and free from contaminants from previous batches, as per the cleaning SOP.
- Verify that the drying equipment is properly calibrated and that all sensors for temperature and humidity are working correctly.
- Prepare the granules for drying by ensuring they have been adequately mixed and that the binder solution is uniformly distributed.
- Check the moisture content of the granules before beginning the drying process. The initial moisture content should be within the specified range (typically 20-30% depending on the formulation).
5.2 Setting Up the Drying Equipment
- Set the temperature and airflow rate of the drying equipment according to the process specifications for the granulation batch.
- For fluidized bed dryers, adjust the airflow rate and temperature to ensure uniform drying and prevent overheating of the granules.
- For tray dryers, ensure the trays are properly loaded with granules in a single layer, with adequate spacing to allow for proper air circulation.
- Ensure that the drying environment is controlled to maintain the desired humidity levels, preventing excessive moisture loss or contamination.
5.3 Monitoring Moisture Content During Drying
- Monitor the moisture content of the granules at regular intervals during the drying process, using a moisture analyzer or a suitable drying method (e.g., Karl Fischer titration).
- Ensure that the moisture content does not exceed the acceptable limits, which typically range from 1% to 5% for most tablet formulations.
- If the moisture content is above the target range, extend the drying time or increase the airflow rate to achieve the required moisture level.
- If the moisture content is too low, decrease the drying temperature or airflow rate to avoid over-drying the granules.
- Record all moisture content measurements in the batch record (Annexure-1), including time and process parameters.
5.4 Adjustments and Corrections
- If moisture levels are too high, stop the process and allow the granules to continue drying under controlled conditions until the desired moisture content is achieved.
- If the granules are over-dried and the moisture content falls below the specified range, adjust the temperature and airflow to rehydrate the granules by adding a controlled amount of binder solution.
- Monitor the granules for any signs of cracking or disintegration that could indicate excessive drying. If any such issues are identified, adjust the drying process to reduce the temperature or airflow rate.
5.5 Final Moisture Content Check
- Once the granules reach the target moisture content, conduct a final moisture check to verify consistency across the batch.
- Confirm that the granules have reached the desired moisture content as per the product specifications, typically between 1% and 5% moisture content, depending on the formulation.
- Check the granules for uniformity in size and texture. Any irregularities or moisture issues should be documented and investigated.
- Once the desired moisture content is verified, proceed to the next stage in tablet manufacturing or store the granules in a controlled environment for future use.
5.6 Documentation and Record-Keeping
- Document all drying process parameters, including temperature, airflow rate, moisture content, and drying time, in the batch record (Annexure-2).
- Ensure that any adjustments made to the drying process (e.g., temperature or airflow) are recorded in the batch record along with the reasons for these changes.
- Review the batch records for completeness and compliance with the required specifications. Ensure that records are signed off by the responsible personnel and reviewed by QA.
- Maintain the batch records, including moisture content logs, for audit purposes and regulatory compliance.
5.7 Equipment Shutdown and Cleaning
- After the drying process is complete, shut down the equipment following the standard operating procedure for equipment shutdown.
- Clean the drying equipment thoroughly to prevent cross-contamination, ensuring that all moisture, product residues, and cleaning agents are removed.
- Record the cleaning activities in the cleaning log and ensure that the equipment is ready for the next batch of granules.
6. Abbreviations
- SOP: Standard Operating Procedure
- GMP: Good Manufacturing Practice
- QC: Quality Control
- QA: Quality Assurance
- API: Active Pharmaceutical Ingredient
7. Documents
- Batch Record (Annexure-1)
- Moisture Content Log (Annexure-2)
- Equipment Cleaning Log (Annexure-3)
8. References
- 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
- EU GMP Guidelines Part I – Basic Requirements for Medicinal Products
- ICH Q7 – Good Manufacturing Practice Guide for Active Pharmaceutical Ingredients
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Batch Record
| Batch Number | Granule Type | Moisture Content (%) | Drying Temperature (°C) | Remarks |
|---|---|---|---|---|
| Batch 001 | Granule A | 4.5% | 50°C | Within specifications |
| Batch 002 | Granule B | 3.2% | 48°C | Adjusted moisture level |
Annexure-2: Moisture Content Log
| Batch Number | Granule Type | Moisture Content (%) | Sampling Time | Remarks |
|---|---|---|---|---|
| Batch 001 | Granule A | 4.5% | 12:00 PM | Within specifications |
| Batch 002 | Granule B | 3.2% | 2:00 PM | Adjusted moisture content |
Annexure-3: Equipment Cleaning Log
| Cleaning Date | Equipment | Cleaning Type | Performed By | Remarks |
|---|---|---|---|---|
| 01/03/2025 | Fluidized Bed Dryer | Routine Cleaning | John Doe | Performed as per SOP |
| 15/04/2025 | Tray Dryer | Maintenance Cleaning | Jane Smith | No issues found |
Revision History:
| Revision Date | Revision No. | Revision Details | Reason for Revision | Approved By |
|---|---|---|---|---|
| 01/01/2024 | 1.0 | Initial Version | New SOP Creation | QA Head |
| 01/02/2025 | 2.0 | Updated Drying Parameters | Optimization of Granule Drying | QA Head |