Procedure for Adding Viscosity Modifiers in the Mixing Process
| Department | Manufacturing/Production/Quality Assurance (QA)/Quality Control (QC)/Research and Development (R&D) |
|---|---|
| SOP No. | SOP/Ointment/193 |
| Supersedes | V 1.0 |
| Page No. | Page X of Y |
| Issue Date | [Insert Issue Date] |
| Effective Date | [Insert Effective Date] |
| Review Date | [Insert Review Date] |
1. Purpose
The purpose of this Standard Operating Procedure (SOP) is to define a systematic approach for adding viscosity modifiers in the mixing process of pharmaceutical ointments. Proper incorporation of viscosity modifiers ensures batch uniformity, stability, and optimal spreadability of the final product.
2. Scope
This SOP applies to all personnel involved in the preparation, addition, and quality control of viscosity modifiers in the Manufacturing, Production, Quality Assurance (QA), Quality Control (QC), and Research and Development (R&D) departments.
3. Responsibilities
- Production Supervisor: Ensures adherence to viscosity modifier addition protocol.
- Process Operator: Monitors and controls mixing conditions for proper dispersion.
- QA Officer: Verifies the consistency of the batch after viscosity modification.
- QC Analyst: Conducts viscosity and homogeneity tests.
- Maintenance Engineer: Ensures mixing equipment operates within defined parameters.
4. Accountability
The Production Manager is accountable for ensuring that all viscosity modifier addition procedures comply with GMP, FDA, ICH, WHO, and company policies.
5. Procedure
5.1 Selection of Viscosity Modifiers
- Common viscosity modifiers used in ointment manufacturing include:
- Carbomers
- Hydroxyethyl cellulose (HEC)
- Xanthan gum
- Polyacrylic acid derivatives
- Silica-based thickeners
- Ensure that the
selected viscosity modifier is compatible with the formulation.
Document selection in the **Viscosity Modifier Selection Log (Annexure-1).**
5.2 Preparation Before Addition
- Ensure that all required ingredients and excipients are available and within specifications.
- Verify the calibration of weighing balances and mixing equipment.
- Adjust the mixing speed based on the viscosity modifier type.
- Record pre-addition checks in the **Pre-Addition Checklist (Annexure-2).**
5.3 Addition Process
- Gradually introduce the viscosity modifier into the mixing tank.
- Maintain an optimal **mixing speed between 100-300 RPM** to avoid clumping.
- If required, pre-disperse the viscosity modifier in a suitable solvent before addition.
- Ensure even dispersion by **mixing continuously for 15-30 minutes.**
- Document addition parameters in the **Viscosity Modifier Addition Log (Annexure-3).**
5.4 Quality Control Testing
- Measure viscosity using a **Brookfield Viscometer or equivalent.**
- Conduct **homogeneity tests** to confirm even distribution of the modifier.
- Compare viscosity values against predetermined specifications.
- Document all test results in the **Viscosity Testing Log (Annexure-4).**
6. Abbreviations
- GMP – Good Manufacturing Practices
- QA – Quality Assurance
- QC – Quality Control
- ICH – International Council for Harmonisation
- FDA – Food and Drug Administration
7. Documents
- Viscosity Modifier Selection Log (Annexure-1)
- Pre-Addition Checklist (Annexure-2)
- Viscosity Modifier Addition Log (Annexure-3)
- Viscosity Testing Log (Annexure-4)
8. References
- ICH Q8 – Pharmaceutical Development Guidelines
- FDA Guidance on Topical Formulation Processing
- WHO Guidelines on Manufacturing Quality Control
9. SOP Version
Version 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Viscosity Modifier Selection Log
| Date | Batch No. | Modifier Used | Quantity (g) | QA Approval |
|---|
Annexure-2: Pre-Addition Checklist
| Date | Batch No. | Equipment Checked | Materials Verified | QA Approval |
|---|
Annexure-3: Viscosity Modifier Addition Log
| Date | Batch No. | Modifier Added | Mixing Speed (RPM) | QA Approval |
|---|
Annexure-4: Viscosity Testing Log
| Date | Batch No. | Viscosity (cP) | Test Equipment | QA Approval |
|---|
12. Revision History
| Revision Date | Revision No. | Details | Reason | Approved By |
|---|---|---|---|---|
| 02/02/2025 | 2.0 | Expanded Viscosity Modifier Addition Guidelines | Regulatory Compliance | QA Head |