Standard Operating Procedure for Clarity and Opalescence Testing of Elixir Formulations
| Department | Elixir Department |
|---|---|
| SOP No. | SOP/ELX/219/2025 |
| Supersedes | SOP/ELX/219/2022 |
| Page No. | Page 1 of 7 |
| Issue Date | 11/04/2025 |
| Effective Date | 15/04/2025 |
| Review Date | 11/04/2026 |
1. Purpose
To describe the procedure for evaluating the clarity and opalescence of elixir formulations to ensure compliance with product specifications and patient acceptability standards.
2. Scope
This SOP applies to the Quality Control Department for visual and instrumental inspection of finished elixir products to detect turbidity, suspended particles, or abnormal coloration.
3. Responsibilities
- QC Analyst:
- Conduct clarity and opalescence tests using specified procedures.
- Record observations in logbooks and report deviations.
- QC Supervisor:
- Verify test results and ensure compliance with product specifications.
- QA Officer:
- Review final reports and approve product release based on results.
4. Accountability
The QC Head is accountable for correct execution of clarity testing. QA Head ensures that clarity-related specifications are met prior to batch release.
5. Procedure
5.1 Sample Preparation
- Withdraw a representative sample of the elixir (minimum 25 mL).
- Use clean,
transparent, colorless glass tubes or bottles for analysis.
Allow sample to stand undisturbed for 5 minutes to eliminate air bubbles.
5.2 Visual Clarity Test (Against Black and White Background)
- Inspect the sample against a well-lit background that is half black and half white.
- Hold the sample at eye level and examine for:
- Opalescence or turbidity
- Foreign particles or sedimentation
- Color consistency
- Record observations and classify the sample as:
- Clear: No visible particles, no opalescence
- Slightly Opalescent: Barely visible haze
- Opalescent: Hazy or turbid with visible particles
- Fail: Presence of foreign matter or unacceptable haze
5.3 Comparative Testing (Optional Instrumental Method)
- Use a calibrated turbidity meter (if available).
- Measure turbidity in Nephelometric Turbidity Units (NTU).
- Acceptance Criteria (if defined):
- NTU ≤ 5: Clear
- NTU > 5 to ≤ 10: Slightly Opalescent
- NTU > 10: Reject
5.4 Acceptance Criteria
- The sample should appear clear and free of visible particles when observed under prescribed conditions.
- Minor opalescence may be acceptable if justified and specified in the product specification.
5.5 Documentation
- Record all results in the Clarity and Opalescence Logbook (Annexure-1).
- Include sample ID, batch number, observer name, and date of analysis.
6. Abbreviations
- SOP: Standard Operating Procedure
- QC: Quality Control
- QA: Quality Assurance
- NTU: Nephelometric Turbidity Unit
7. Documents
- Clarity and Opalescence Logbook (Annexure-1)
- Instrument Calibration Record (if turbidity meter is used)
- Batch Manufacturing Record (BMR)
8. References
- USP General Chapter <790> – Visible Particulates in Injections (adapted for oral liquid)
- Ph. Eur. 2.2.1 – Clarity and Degree of Opalescence of Liquids
- 21 CFR Part 211.160 – Laboratory Controls
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Clarity and Opalescence Logbook
| Date | Batch No. | Observation | Classification | Tested By | Verified By |
|---|---|---|---|---|---|
| 11/04/2025 | ELX-0425-037 | No visible particles, slight haze | Slightly Opalescent | Rajesh Kumar | Sunita Reddy |
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 |
| 11/04/2025 | 2.0 | Added turbidity meter option and updated criteria | Method Expansion | QA Head |