Standard Operating Procedure for Moisture Content Testing in Granules and Tablets
| Department | Tablet |
|---|---|
| SOP No. | SOP/TAB/085/2025 |
| Supersedes | SOP/TAB/085/2022 |
| Page No. | Page 1 of 7 |
| Issue Date | 01/03/2026 |
| Effective Date | 06/03/2026 |
| Review Date | 01/03/2027 |
1. Purpose
To outline the procedure for moisture content testing in granules and tablets to ensure the proper moisture levels are maintained, preventing issues with stability, dissolution, and shelf life.
2. Scope
This SOP applies to the moisture content testing of both granules and tablets at various stages of manufacturing to verify that moisture levels are within the acceptable limits specified in the batch record or pharmacopeial guidelines.
3. Responsibilities
- Manufacturing Personnel: Responsible for providing the samples of granules and tablets for moisture content testing and ensuring proper storage conditions.
- Quality Control (QC): Responsible for conducting moisture content testing, recording the results, and ensuring compliance with the specifications.
- Quality Assurance (QA): Ensures the testing procedure is followed and reviews the results for batch approval and release.
4. Accountability
The QC Manager is accountable for ensuring that moisture content testing is conducted in compliance with this SOP and for reporting the results. The QA Manager is responsible
for reviewing the results and approving the batch for release.
5. Procedure
5.1 Sample Collection
- Collect a representative sample of granules or tablets from the batch, as specified in the batch record.
- The sample should consist of 6 tablets or an appropriate amount of granules (or as specified in the batch record or pharmacopeial guidelines).
- Ensure that the tablets or granules are free from defects, contamination, or other visible issues.
- Label the sample appropriately for identification during testing.
5.2 Preparation of Moisture Content Testing Apparatus
- Ensure that the moisture content testing apparatus, such as a moisture analyzer or an oven, is calibrated and functioning properly.
- Prepare the sample holder or petri dish and ensure that the balance used for weighing is accurate and properly calibrated.
5.3 Performing Moisture Content Test
- Weigh the sample (e.g., 5–10 grams of granules or 6 tablets) and record the initial weight in the batch record (Annexure-1).
- If using a moisture analyzer, place the sample on the instrument’s platform and follow the instructions to test the moisture content, ensuring that the moisture analyzer’s temperature is set as per the method (typically 105°C to 110°C for tablets).
- If using an oven method, place the sample in a preheated oven at the designated temperature (typically 105°C) for the specified time (usually 2–4 hours) and then cool it in a desiccator before weighing it again.
- For both methods, the moisture content is calculated based on the weight loss after drying.
5.4 Data Recording and Calculation
- Record the final weight of the sample after drying and calculate the moisture content as follows:
- Moisture Content (%) = (Initial Weight – Final Weight) / Initial Weight × 100
- Ensure that the moisture content is within the acceptable range specified in the batch record or pharmacopeial guidelines (typically ≤ 2% for tablets, but this may vary).
- Document the calculated moisture content in the batch record (Annexure-1) along with the testing method and any observations.
5.5 Moisture Content Acceptance Criteria
- Ensure that the moisture content of the granules or tablets falls within the specified limits. The typical range for tablets is between 1–2%, but this may vary depending on the product.
- If the moisture content exceeds the specified limits, investigate the cause, and document the findings in the deviation report (Annexure-2). Corrective actions should be implemented as necessary.
5.6 Documentation and Record-Keeping
- Document the moisture content testing results, including the initial and final weights, moisture content, and method used, in the batch record (Annexure-1).
- Record any deviations from the moisture content specifications in the deviation report (Annexure-2), along with corrective actions taken.
- Ensure all records are signed, dated, and stored according to the company’s record retention policy for future audits and inspections.
5.7 Post-Test Cleanup
- Clean the moisture content testing apparatus, including the moisture analyzer or oven, according to the manufacturer’s instructions and the company’s cleaning SOP.
- Ensure that all equipment is properly stored and maintained in good working condition for future use.
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)
- Deviation Report (Annexure-2)
8. References
- USP <731> – Loss on Drying
- 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
- European Pharmacopoeia (EP) – Loss on Drying
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 | Tablet Sample | Initial Weight (g) | Final Weight (g) | Moisture Content (%) |
|---|---|---|---|---|
| Batch 001 | 6 tablets | 5.20 | 5.10 | 1.92% |
Annexure-2: Deviation Report
| Deviation Date | Batch Number | Deviation Description | Corrective Action | Responsible Person |
|---|---|---|---|---|
| 10/12/2025 | Batch 001 | Moisture content exceeded specification | Adjusted granulation and drying process | John Doe |
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 Moisture Testing Method | Refined moisture testing parameters | QA Head |