critical to ensure reproducibility and regulatory compliance during dissolution testing.

2. Scope

This SOP applies to all dissolution media prepared and used within the Analytical Method Development (AMD) department for dissolution testing of pharmaceutical solid oral dosage forms.

3. Responsibilities

• Analytical Chemist: Responsible for preparation, filtration, degassing, and documentation of dissolution media.
• Lab Assistant: Assists in washing and setting up filtration and degassing equipment.
• QA Executive: Verifies the integrity and suitability of equipment and process compliance.

4. Accountability

The Head of Analytical Method Development is accountable for ensuring adherence to this SOP during dissolution media preparation to maintain testing consistency and compliance.

5. Procedure

5.1 Media Preparation

1. Prepare required volume of dissolution medium (e.g., 0.1N HCl, acetate buffer pH 4.5, phosphate buffer pH 6.8, water, etc.) according to the relevant dissolution method.
2. Use calibrated pH meter to confirm media pH.
3. Label containers with media type, volume, preparation date, expiry date, and initials.

5.2 Filtration Procedure

1. Use a validated vacuum filtration unit equipped with:
   • 0.45 µm membrane filter (nylon, PVDF, or equivalent)
   • Glass filter holders and clean receiving flask
2. Assemble the filtration system on a clean, vibration-free bench or laminar airflow unit.
3. Pre-rinse the filter membrane with 50 mL of dissolution media before filtration.
4. Filter the media in batches not exceeding 5 L at a time to prevent overpressure or leakage.
5. Transfer filtered media into clean, labeled storage carboys or vessels.

5.3 Degassing Methods

Choose any one of the following degassing methods depending on method validation requirements:

1. Vacuum Degassing:
   • Apply vacuum at 300–500 mmHg for 5–10 minutes under gentle stirring.
   • Use vacuum desiccator or degassing assembly with stir bar.
2. Helium Sparging:
   • Sparge media with helium gas at low flow rate (~100 mL/min) for 10–15 minutes.
   • Use only approved helium gas cylinder with regulator.
3. Ultrasonication:
   • Place media container in ultrasonic bath for 15–20 minutes.
   • Ensure consistent bath temperature and no bubble formation post-sonication.

5.4 Storage and Handling

1. Use filtered and degassed media on the same day of preparation.
2. Store media at 20–25°C and avoid exposure to sunlight and dust.
3. If media is not used within 24 hours, discard and re-prepare fresh medium.

5.5 Documentation

1. Enter preparation details in Annexure-1: Dissolution Media Preparation Log.
2. Record degassing method, equipment ID, and any deviations in Annexure-2.
3. QA to verify record during batch review or inspection.

6. Abbreviations

• SOP: Standard Operating Procedure
• QA: Quality Assurance
• PVDF: Polyvinylidene Fluoride
• µm: Micrometer

7. Documents

1. Dissolution Media Preparation Log – Annexure-1
2. Degassing Method and Equipment Record – Annexure-2
3. Filter Integrity Checklist – Annexure-3

8. References

• USP General Chapter <711>: Dissolution
• FDA Guidance: Dissolution Testing for Immediate Release Solid Oral Dosage Forms
• ICH Q6A: Specifications – Test Procedures and Acceptance Criteria

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Namrata Kulkarni	Devendra Patil	Sunita Reddy
Designation	Analyst	QA Reviewer	Head – AMD
Department	Analytical Method Development	QA	Analytical Method Development

11. Annexures

Annexure-1: Dissolution Media Preparation Log

Date	Media Type	pH	Volume	Prepared By	QA Verified
21/05/2025	Phosphate Buffer	6.8	9000 mL	Namrata K.	Devendra P.

Annexure-2: Degassing Record

Date	Method	Equipment ID	Duration	Performed By
21/05/2025	Vacuum	DG/VAC/01	10 min	Namrata K.

Annexure-3: Filter Integrity Checklist

Date	Filter Type	Integrity Test Result	Remarks
21/05/2025	0.45 µm PVDF	Pass	Rinsed prior to use

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
21/05/2025	2.0	Included additional degassing options and annexures	Annual SOP Review	Sunita Reddy
12/05/2022	1.0	Initial Release	New SOP	QA Head