Standard Operating Procedure for Granule Moisture Content Testing Before Compression
| Department | Quality Control |
|---|---|
| SOP No. | SOP/TAB/127/2025 |
| Supersedes | SOP/TAB/127/2022 |
| Page No. | Page 1 of 6 |
| Issue Date | 01/03/2026 |
| Effective Date | 06/03/2026 |
| Review Date | 01/03/2027 |
1. Purpose
To define the procedure for testing the moisture content of granules before compression, ensuring that the granules meet the required moisture specifications for further processing.
2. Scope
This SOP applies to the testing of moisture content in granules before compression during tablet manufacturing, ensuring optimal moisture levels for compression and subsequent tablet quality.
3. Responsibilities
- Quality Control (QC): Responsible for performing moisture content tests on granules, recording the results, and ensuring that the moisture content is within the required specifications.
- Granulation Operator: Responsible for taking samples of the granules and providing them to QC for moisture testing during the granulation process.
- Quality Assurance (QA): Ensures that moisture content testing is conducted according to this SOP and reviews the results for compliance with specifications.
4. Accountability
The QC Manager is accountable for ensuring that moisture content testing is performed accurately and according to this SOP. The QA Manager is responsible for reviewing the results to ensure
compliance with internal and regulatory standards.
5. Procedure
5.1 Sample Collection
- During the granulation process, collect a representative sample of the granules at regular intervals, typically every 15 minutes or after processing each set of granules.
- The sample size should be sufficient to ensure accurate results, typically 100 grams of granules per sample.
5.2 Moisture Content Testing Method
- Use the appropriate method for measuring moisture content, such as the loss on drying (LOD) method or a moisture analyzer, to measure the moisture level in the granules.
- If using the LOD method, weigh the sample and place it in a preheated oven at the prescribed temperature (typically 105°C) for a specified time (typically 1 hour) to remove moisture.
- Weigh the sample again after drying to calculate the moisture content based on the weight difference.
- If using a moisture analyzer, follow the manufacturer’s instructions to determine the moisture content directly.
5.3 Monitoring and Adjustments
- If the moisture content of the granules is outside the acceptable range (typically 2–4%), adjust the granulation process as necessary to achieve the desired moisture content.
- Adjustments may include increasing or decreasing the binder solution, altering drying time, or adjusting granulator settings to ensure optimal moisture content.
- After making adjustments, re-sample and re-test the granules to ensure that the moisture content is within the required specification.
5.4 Monitoring Frequency
- Moisture content should be tested at regular intervals throughout the granulation process. Typically, testing is performed every 15 minutes or after processing every set of granules.
- If any irregularities or deviations are observed, increase the frequency of testing until the issue is resolved.
5.5 Documentation
- Record the following information for each moisture content test:
- Sample number and time of collection
- Moisture content measurement
- Deviation from the target moisture content, if any
- Adjustments made to the process, if applicable
- Document all test results and corrective actions taken in the batch record (Annexure-2).
- Ensure that all records are signed and dated by the responsible personnel and reviewed by QA for compliance.
5.6 Acceptance Criteria
- The moisture content of the granules should be within the specified range (typically 2–4% moisture content).
- If the moisture content is outside the acceptable limits, the batch may need to be rejected or reworked. Adjustments should be made to bring the granules within the required moisture range.
5.7 Post-Granulation Actions
- Once the granules meet the required moisture content, proceed with the next steps in tablet manufacturing, such as compression, coating, and packaging.
- Ensure that any adjustments made to the granulation process are recorded, and the equipment is cleaned and calibrated as required.
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-2)
- Deviation Report (Annexure-1)
8. References
- USP <731> – Loss on Drying (LOD)
- 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
- European Pharmacopoeia (EP) – Specifications for Granule Moisture Content
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Deviation Report
| Deviation Date | Batch Number | Deviation Description | Corrective Action | Responsible Person |
|---|---|---|---|---|
| 15/12/2025 | Batch 001 | Granules had moisture content > 5% | Adjusted binder solution and drying time | John Doe |
Annexure-2: Batch Record
| Sample Number | Moisture Content (%) | Time of Test | Action Taken |
|---|---|---|---|
| Sample 1 | 3.5 | 10:30 AM | Accepted |
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 sampling and testing procedures | Improved uniformity checking | QA Head |