Procedure for Conducting Homogeneity Studies of Ointments
| Department | Research and Development (R&D)/Quality Control |
|---|---|
| SOP No. | FD-015 |
| 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 establish a standardized approach for conducting homogeneity studies of ointments. This ensures uniform distribution of active pharmaceutical ingredients (APIs) and excipients throughout the formulation to maintain product consistency and efficacy.
2. Scope
This SOP applies to the Research and Development (R&D) and Quality Control (QC) departments responsible for evaluating the homogeneity of ointments during formulation development and manufacturing. The procedure includes sample preparation, analytical testing, and evaluation criteria.
3. Responsibilities
- Formulation Scientist: Conducts the homogeneity study and records results.
- Quality Control (QC) Analyst: Performs analytical testing to verify uniformity.
- Quality Assurance (QA) Personnel: Ensures compliance with standard procedures.
- R&D Head: Reviews and approves homogeneity study reports before product finalization.
4. Accountability
The R&D and QC Managers are accountable for ensuring that homogeneity studies are conducted per regulatory and quality standards.
5. Procedure
5.1 Sample Collection
- Collect samples from different points of the batch:
- Top
- Middle
- Bottom
- Ensure that at least three replicates are collected from each section.
- Label each sample with batch number, collection point, and date.
5.2 Visual Inspection
- Observe the samples under
normal and magnified light.
Check for uniform color, texture, and phase separation.
Record any inconsistencies in the Homogeneity Testing Log.
5.3 Chemical Analysis
- Perform assay testing using High-Performance Liquid Chromatography (HPLC) or Ultraviolet (UV) Spectroscopy.
- Measure API concentration in each sample and compare with theoretical values.
- Calculate the percentage variation among different sample locations.
- Ensure the variation is within the acceptable limit (e.g., ±5%).
5.4 Microscopic Examination
- Spread a thin layer of the ointment on a glass slide.
- Examine the uniformity of dispersed API particles under a microscope.
- Document any visible inconsistencies.
5.5 Rheological (Viscosity) Testing
- Measure viscosity at different shear rates using a Brookfield Viscometer.
- Compare results to expected values to confirm consistency.
5.6 Homogeneity Evaluation Criteria
- Acceptable uniformity: API concentration variance within ±5% of label claim.
- No phase separation or particle agglomeration.
- Consistent viscosity readings across different sections.
5.7 Documentation and Reporting
- Record all observations and test results in the Homogeneity Testing Log.
- Summarize findings in the Homogeneity Study Report.
- Obtain approval from the R&D Head and QA before proceeding with further formulation development.
6. Abbreviations
- API – Active Pharmaceutical Ingredient
- QC – Quality Control
- QA – Quality Assurance
- HPLC – High-Performance Liquid Chromatography
- UV – Ultraviolet Spectroscopy
7. Documents
- Homogeneity Testing Log (Annexure-1)
- Homogeneity Study Report (Annexure-2)
8. References
- ICH Q2(R1) Validation of Analytical Procedures
- USP <905> Uniformity of Dosage Units
- WHO GMP Guidelines for Pharmaceutical Manufacturing
- 21 CFR Part 211 – Current Good Manufacturing Practices
9. SOP Version
Version 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Homogeneity Testing Log
| Date | Batch Number | Sample Location | Test Parameter | Result | Verified By |
|---|---|---|---|---|---|
| 01/02/2025 | OINT-001 | Top | API Assay (%) | 99.2% | QA Officer |
| 01/02/2025 | OINT-001 | Middle | API Assay (%) | 98.8% | QA Officer |
| 01/02/2025 | OINT-001 | Bottom | API Assay (%) | 99.0% | QA Officer |
Annexure-2: Homogeneity Study Report
| Date | Batch Number | Test Parameter | Specification | Result | Final Status |
|---|---|---|---|---|---|
| 01/02/2025 | OINT-001 | Viscosity | 1000-2000 cP | 1500 cP | Pass |
| 02/02/2025 | OINT-002 | API Uniformity | 98-102% | 99.0% | Pass |
12. Revision History:
| Revision Date | Revision No. | Details of Revision | Reason for Revision | Approved By |
|---|---|---|---|---|
| 01/01/2024 | 1.0 | Initial Version | New SOP | QA Head |
| 01/02/2025 | 2.0 | Updated SOP Format | Standardization of Document | QA Head |