Standard Operating Procedure for Adhesion Testing of Coated Tablets During Production
| Department | Tablet |
|---|---|
| SOP No. | SOP/TAB/147/2025 |
| Supersedes | SOP/TAB/147/2022 |
| Page No. | Page 1 of 6 |
| Issue Date | 01/03/2026 |
| Effective Date | 06/03/2026 |
| Review Date | 01/03/2027 |
1. Purpose
To establish the procedure for performing adhesion testing of coated tablets during production to ensure that the film coating adheres properly and meets the required specifications for tablet durability and drug release.
2. Scope
This SOP applies to the testing of adhesion properties of the coating on tablets during the coating process to ensure that the tablets meet the required quality standards.
3. Responsibilities
- Quality Control (QC): Responsible for performing the adhesion tests and ensuring that the coating meets the specified adhesion criteria.
- Coating Operator: Responsible for collecting the samples of coated tablets for adhesion testing and ensuring the correct procedure is followed.
- Quality Assurance (QA): Ensures compliance with this SOP, reviews test results, and approves any corrective actions or deviations from the standard.
4. Accountability
The QC Manager is accountable for ensuring that adhesion tests are performed regularly during the tablet coating process. The QA Manager ensures that the testing process follows the SOP and verifies the results for compliance with the required specifications.
5. Procedure
5.1 Sample Collection
- During the coating process, collect random samples of coated tablets from the production batch at defined intervals (e.g., after every 100 kg or batch).
- Ensure that the samples are representative of the entire batch and are collected according to the sampling procedure.
5.2 Adhesion Testing Method Selection
- Choose the appropriate adhesion testing method based on the type of coating used (e.g., tape test, peel test, or crosshatch test).
- Ensure that the selected testing method is suitable for the type of coating and complies with internal or regulatory specifications.
5.3 Performing Adhesion Testing
- For the tape test: Apply a piece of adhesive tape firmly to the surface of the coated tablet, then quickly remove it. Examine the amount of coating that is removed along with the tape.
- For the peel test: Place the tablet on a flat surface, and using a suitable tool, apply a force to peel the coating from the tablet. Measure the amount of coating that is removed and record the result.
- For the crosshatch test: Use a scalpel or similar tool to make a series of intersecting cuts on the coated surface, then apply adhesive tape as described above and record the amount of coating that is removed.
- Record the results of the adhesion test in the batch record (Annexure-2) and note any deviations or issues observed.
5.4 Documentation and Records
- Document the adhesion test results, including the type of test performed, the results, and any deviations, in the batch record (Annexure-2).
- If the adhesion test fails, generate a deviation report (Annexure-1) and take corrective action, such as adjusting the coating process or formulation.
- Ensure that all records are signed, dated, and reviewed by QA personnel.
5.5 Acceptance Criteria
- The adhesion of the coating to the tablet must meet the predefined specifications, such as a minimum percentage of coating remaining after the adhesion test, or specific guidelines for peeling or tape removal.
- If the coating adhesion is below the specified threshold, the batch may need to be rejected, reprocessed, or further investigated.
5.6 Post-Testing Actions
- Once testing is complete, continue with subsequent production steps if the results meet the required specifications.
- If the adhesion test fails, evaluate the root cause, adjust the coating process or formulation, and retest the batch for adhesion before proceeding with further processing.
6. Abbreviations
- SOP: Standard Operating Procedure
- GMP: Good Manufacturing Practice
- QC: Quality Control
- QA: Quality Assurance
7. Documents
- Batch Record (Annexure-2)
- Deviation Report (Annexure-1)
8. References
- USP <701> – Film Coating of Tablets
- 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
- European Pharmacopoeia (EP) – Film Coating Specifications for Tablets
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 | Coating adhesion failed the tape test | Reformulated coating and reprocessed the batch | John Doe |
Annexure-2: Batch Record
| Sample Number | Adhesion Test Result | Action Taken |
|---|---|---|
| Sample 1 | Passed | 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 adhesion test procedure | Improved coating quality control | QA Head |