Standard Operating Procedure for Applying Protective Seal Coating for Sugar-Coated Tablets
| Department | Tablet |
|---|---|
| SOP No. | SOP/TAB/041/2025 |
| Supersedes | SOP/TAB/041/2022 |
| Page No. | Page 1 of 6 |
| Issue Date | 01/09/2025 |
| Effective Date | 06/09/2025 |
| Review Date | 01/09/2026 |
1. Purpose
This SOP outlines the procedure for applying a protective seal coating on sugar-coated tablets. The protective seal coating ensures that the sugar coating remains intact and provides additional protection against environmental factors, such as moisture, while preserving the tablet’s integrity and ensuring its shelf-life.
2. Scope
This SOP applies to the sugar-coated tablet production process, specifically during the application of the protective seal coating. It covers the preparation of the coating solution, the application process, and the required quality checks to ensure that the protective coating is applied correctly.
3. Responsibilities
- Manufacturing Personnel: Responsible for applying the protective seal coating to sugar-coated tablets according to this SOP and ensuring that all equipment is properly set up and calibrated.
- Quality Control (QC): Responsible for monitoring the application process, ensuring that the seal coating meets the required quality specifications, and conducting necessary quality checks on the final product.
- Quality Assurance (QA): Ensures that the seal coating process complies with this SOP and reviews all records and documentation related to the coating process.
4. Accountability
The Production Manager is accountable for overseeing the protective seal coating application process. The QA Manager is responsible for ensuring compliance with quality standards and regulatory requirements, and for reviewing any deviations from the SOP.
5. Procedure
5.1 Pre-Coating Setup
- Ensure that the sugar-coated tablets are fully dried and ready for the application of the protective seal coating.
- Verify that the coating machine, including the spray guns, pan, and air control system, is properly cleaned and calibrated according to the equipment maintenance SOP.
- Prepare the protective seal coating solution by mixing the specified ingredients, which may include film-forming agents, plasticizers, and solvents, according to the formulation sheet.
- Check the temperature and humidity levels of the environment to ensure they are within the specified range for the coating process.
5.2 Application of Protective Seal Coating
- Place the tablets in the coating pan, ensuring that they are evenly distributed to avoid overlapping and ensure uniform coating.
- Set the desired temperature and airflow for the coating process. Typically, a temperature between 40°C and 50°C is used to ensure proper drying of the coating material.
- Begin applying the protective seal coating solution to the tablets, spraying it evenly while rotating the pan to ensure uniform coverage.
- Adjust the spray rate and airflow as necessary to ensure that the coating is applied evenly without over-spraying or causing uneven thickness.
- Monitor the tablet coating thickness during the application process, ensuring that it meets the specified requirements for the final product.
- Allow the tablets to rotate in the pan for an adequate time to ensure that the protective seal coating has dried properly.
5.3 Post-Coating Drying
- After applying the protective seal coating, increase the airflow to facilitate the drying process. Maintain the temperature between 40°C to 50°C during this step.
- Allow sufficient time for the protective coating to dry completely. This step ensures that the tablets are free from any excess moisture and that the seal coating hardens properly.
- Periodically check the tablets for any signs of moisture or tackiness, which may indicate that the drying process is incomplete.
- If any tablets are found to have residual moisture, allow them to dry further under controlled conditions to prevent coating defects or degradation.
5.4 Quality Control Checks
- After the coating and drying process is complete, inspect the tablets for uniformity and quality of the protective seal coating. Tablets should have a smooth, glossy finish without cracks or uneven areas.
- Perform a visual inspection of the tablets to ensure that the protective seal coating is evenly applied, without any visible defects such as peeling or chipping.
- Conduct hardness and friability tests to ensure that the tablets are not overly brittle or too soft, which could indicate an issue with the protective coating or the drying process.
- Document all quality control checks and test results in the batch record (Annexure-1). Record any deviations or issues encountered during the process in the deviation report (Annexure-2).
5.5 Documentation and Record-Keeping
- Ensure that all details of the protective seal coating application, including solution preparation, equipment settings, and quality control checks, are documented in the batch record (Annexure-1).
- Document any deviations from the standard operating procedure in the deviation report (Annexure-2), along with the corrective actions taken.
- Store all batch records, quality control results, and deviation reports for future reference, audits, and regulatory inspections.
5.6 Equipment Cleaning and Maintenance
- After each batch, clean all equipment used in the protective seal coating process, including the coating pan, spray guns, and air control system, according to the equipment cleaning SOP.
- Inspect the equipment regularly for any signs of wear, damage, or contamination. Perform necessary repairs or replacements to maintain optimal performance.
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
- 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 | Tablet Type | Coating Solution | Application Settings | Coating Quality |
|---|---|---|---|---|
| Batch 001 | Tablet A | Seal coat solution: 5% polyvinyl alcohol | Temperature: 45°C, Airflow: 2.0 m³/min | Pass |
| Batch 002 | Tablet B | Seal coat solution: 7% hydroxypropyl methylcellulose | Temperature: 48°C, Airflow: 2.5 m³/min | Pass |
Annexure-2: Deviation Report
| Deviation Date | Batch Number | Deviation Description | Corrective Action | Responsible Person |
|---|---|---|---|---|
| 05/08/2025 | Batch 002 | Uneven coating observed during final inspection | Adjusted airflow and reprocessed tablets | 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 Coating Solution and Application Process | Improved Process Efficiency | QA Head |