Procedure for Homogeneity Testing at Different Stages

Department	Quality Control (QC)/Quality Assurance (QA)/Production
SOP No.	SOP/Ointment/036
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 systematic process for homogeneity testing at different stages of ointment manufacturing. Homogeneity testing ensures uniform distribution of active ingredients, consistency, and quality compliance.

2. Scope

This SOP applies to all ointment batches produced in the manufacturing facility, covering pre-mixing, final mixing, cooling, and filling stages.

3. Responsibilities

• Production Supervisor: Ensures samples are collected at required intervals.
• QC Analyst: Conducts homogeneity testing as per batch specifications.
• QA Personnel: Reviews test results and ensures compliance with GMP standards.
• R&D Scientist: Defines homogeneity testing parameters for each formulation.

4. Accountability

The QA and QC Managers are accountable for ensuring that homogeneity testing is conducted as per GMP standards and properly documented.

5. Procedure

5.1 Sampling for Homogeneity Testing

• Collect representative samples from different parts of the batch:
• Top
• Middle
• Bottom
• Edges of the mixing vessel
• Ensure aseptic handling of samples to avoid contamination.
• Label samples with batch number, sampling location, and stage.

5.2 Homogeneity Testing at Different Stages

5.2.1 Pre-Mixing Stage

• Verify uniform dispersion of active ingredients before heating.
• Perform visual inspection for any signs of separation.
• Check the initial viscosity of the batch.

5.2.2 Final Mixing Stage

• Perform pH and viscosity testing to confirm uniformity.
• Check for particle size distribution using a suitable analyzer.
• Compare test results with pre-defined batch specifications.

5.2.3 Cooling Stage

• Check for phase separation or crystallization.
• Perform homogeneity testing for emulsions.
• Ensure uniform consistency across all sampling locations.

5.2.4 Filling Stage

• Test for weight variation to ensure uniform filling.
• Analyze random filled containers to confirm content uniformity.
• Perform final physical and chemical analysis before batch release.

5.3 Acceptance Criteria for Homogeneity

• Active ingredient distribution should be within ±5% of the target concentration.
• pH and viscosity must match the batch specification.
• No signs of phase separation, air entrapment, or inconsistencies.
• Test results should comply with pharmacopeial requirements (USP, BP, IP).

5.4 Documentation and Approval

• Record test results in the Homogeneity Test Log.
• QA must verify and approve homogeneity before batch release.
• Retain test samples for stability analysis if required.

6. Abbreviations

• GMP – Good Manufacturing Practices
• QA – Quality Assurance
• QC – Quality Control
• USP – United States Pharmacopeia
• BP – British Pharmacopeia
• IP – Indian Pharmacopeia

7. Documents

• Homogeneity Test Log (Annexure-1)
• In-Process Quality Control Report (Annexure-2)

8. References

• WHO GMP Guidelines for Pharmaceutical Manufacturing
• 21 CFR Part 211 – Current Good Manufacturing Practices
• USP/BP/IP Standard Test Methods

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 Test Log

Date	Batch Number	Sampling Location	Test Parameter	Specification	Result	Verified By
01/02/2025	SOP/Ointment/001	Top	Active Ingredient %	95-105%	98%	QA Officer
02/02/2025	SOP/Ointment/002	Bottom	pH	5.5-7.0	6.3	QA Officer

Annexure-2: In-Process Quality Control Report

Date	Batch Number	Stage	Test Parameter	Specification	Result	Final Status
01/02/2025	SOP/Ointment/001	Final Mixing	Viscosity	1000-2000 cP	1500 cP	Pass
02/02/2025	SOP/Ointment/002	Cooling	Phase Separation	None	None	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