Standard Operating Procedure for Screening Polymers for Capsule Coating
Department | Capsule Manufacturing |
---|---|
SOP No. | SOP/CM/024/2025 |
Supersedes | SOP/CM/024/2022 |
Page No. | Page 1 of 6 |
Issue Date | 01/02/2025 |
Effective Date | 05/02/2025 |
Review Date | 01/02/2026 |
1. Purpose
The purpose of this SOP is to outline the procedure for screening and selecting polymers suitable for capsule coating to ensure optimal capsule performance, including controlled release, stability, and protection of the active pharmaceutical ingredient (API).
2. Scope
This SOP applies to the screening of all polymers used in capsule coating formulations, including polymers for immediate release, controlled release, and enteric coatings.
3. Responsibilities
- Formulation Development Team: Responsible for screening, testing, and selecting appropriate polymers for capsule coating based on performance criteria.
- Quality Control (QC) Team: Ensures that the selected polymers meet the required standards for quality, consistency, and performance in capsule coatings.
- Quality Assurance (QA) Team: Oversees compliance with SOPs and regulatory requirements during polymer screening and selection processes.
- Procurement Team: Responsible for sourcing the selected polymers from approved suppliers and ensuring their availability for the formulation process.
4. Accountability
The Formulation Development Supervisor is accountable for ensuring the proper screening and selection of polymers for capsule coatings, while the QA Manager is responsible for ensuring compliance with regulatory guidelines and internal quality standards.
5. Procedure
5.1 Identifying Requirements for Coating
Ensure that the functional requirements for the capsule coating are clearly defined:
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Coating Functionality
- Determine the primary function of the coating (e.g., immediate release, delayed release, or controlled release).
- Consider the stability, protection, and aesthetic requirements of the coating, such as color, gloss, and texture.
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API Compatibility
- Assess the compatibility of the API with the polymer options to ensure that no degradation, interaction, or instability occurs during the coating process.
5.2 Selecting Suitable Polymers
Screen and select polymers based on the defined coating requirements:
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Polymer Types
- Choose polymers based on their release characteristics, such as natural and synthetic polymers for different types of coating (e.g., HPMC for controlled release, Eudragit for enteric coatings).
- Consider the polymer’s solubility in water, pH sensitivity, and ability to form a uniform coating film on the capsule.
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Polymer Functional Properties
- Assess the properties of the polymer such as viscosity, film-forming capability, and ability to protect the API from moisture or light.
- Consider the ease of application, including sprayability and the drying process of the polymer when used in coating equipment.
5.3 Conducting Polymer Testing
Test selected polymers for performance and compatibility with capsule formulations:
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Film Formation Test
- Test the polymer’s ability to form a smooth and uniform coating on the capsule using a film-forming test.
- Evaluate the appearance, smoothness, and uniformity of the coating under visual inspection and microscopy.
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Dissolution Testing
- Conduct dissolution tests on capsules coated with the selected polymers to evaluate the release profile of the API.
- Monitor the release rate and compare the results against the desired specifications for immediate or controlled release.
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Stability Testing
- Conduct accelerated and long-term stability testing on the coated capsules to assess the effect of the coating on the stability of the API under various storage conditions (temperature, humidity, etc.).
- Ensure that the polymer maintains the integrity of the capsule coating during the shelf life of the product.
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Compatibility Study
- Perform compatibility studies between the polymer and excipients used in the capsule fill to ensure there are no adverse interactions or instability in the final product.
5.4 Optimizing Polymer Formulation
Optimize the formulation of the polymer coating based on the testing results:
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Polymer Concentration
- Adjust the concentration of the selected polymer to achieve the desired coating thickness and performance.
- Ensure that the polymer solution or dispersion is uniform and free of particles that could affect the application process.
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Plasticizer Selection
- Select appropriate plasticizers to improve the flexibility and workability of the polymer coating, preventing cracking or peeling.
- Test different plasticizers to determine the optimal combination for a flexible and durable coating.
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Coating Process Parameters
- Optimize the coating process parameters such as spray rate, drying temperature, and spray distance to ensure consistent coating quality.
- Ensure that the coating process is scalable for large-scale manufacturing while maintaining product quality.
5.5 Final Evaluation and Selection of Polymer
Evaluate the final selection of the polymer based on all testing results:
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Final Testing
- Conduct final dissolution and stability tests on the polymer-coated capsules to ensure that the formulation meets all quality specifications for release and stability.
- Confirm that the coating provides the required functionality such as controlled release or enteric protection.
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Polymer Approval
- Approve the selected polymer based on the results of all testing and evaluation, ensuring it meets regulatory standards and performance specifications.
5.6 Documentation and Record-Keeping
Ensure proper documentation of the polymer screening and selection process:
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Documentation of Polymer Selection
- Document all polymer screening, testing, and evaluation results in a detailed report that includes the selected polymer, the testing methods used, and the final recommendations.
- Ensure that all documentation is reviewed and signed off by the formulation team and the QA team.
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Record Retention
- Ensure that all records, including test data, approval forms, and any deviations, are securely stored for future reference and regulatory audits.
6. Abbreviations
- SOP: Standard Operating Procedure
- API: Active Pharmaceutical Ingredient
- QA: Quality Assurance
- QC: Quality Control
- GMP: Good Manufacturing Practice
- HPLC: High-Performance Liquid Chromatography
- FTIR: Fourier Transform Infrared Spectroscopy
- DSC: Differential Scanning Calorimetry
7. Documents
- Polymer Screening Report (Annexure-1)
- Polymer Compatibility Study (Annexure-2)
- Polymer Coating Test Results (Annexure-3)
8. References
- USP <711> – Dissolution Testing
- ICH Q1A (R2) – Stability Testing of New Drug Substances and Products
- FDA Guidance for Industry: Capsule Coating
9. SOP Version
Version: 2.0
10. Approval Section
Prepared By | Checked By | Approved By | |
---|---|---|---|
Signature | |||
Date | |||
Name | |||
Designation | |||
Department |
11. Annexures
Annexure-1: Polymer Screening Report
Date | Polymer Name | Study Type | Result |
---|---|---|---|
03/02/2025 | Polymer-123 | Compatibility Test | Stable with API |
Annexure-2: Polymer Compatibility Study
Date | Polymer | API | Test Method | Outcome |
---|---|---|---|---|
04/02/2025 | Polymer-123API-456 | DSC | No incompatibility |
Annexure-3: Polymer Coating Test Results
Date | Test Type | Result | Action Taken |
---|---|---|---|
05/02/2025 | Dissolution Test | Pass | Formulation approved |
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 polymer selection process | Standardization | QA Head |