using USP Apparatus I (Basket) or II (Paddle), involving staged media to simulate gastrointestinal conditions.

2. Scope

This SOP applies to Analytical Method Development and Quality Control departments involved in formulation development, stability testing, and regulatory submissions for delayed release solid oral dosage forms.

3. Responsibilities

• Formulation Scientist: Provides dissolution profile targets and enteric coating specifications.
• Analytical Scientist: Develops, optimizes, and validates the method.
• QA Executive: Ensures documentation and regulatory compliance for method development and application.

4. Accountability

The Head of Analytical Method Development is accountable for ensuring validated dissolution methods align with ICH, USP, and regulatory expectations for delayed release formulations.

5. Procedure

5.1 Apparatus and Conditions

• Apparatus: USP Type I (Basket) or Type II (Paddle)
• Speed: Typically 100 rpm (basket) or 50–75 rpm (paddle)
• Temperature: 37.0 ± 0.5°C

5.2 Dissolution Media

1. Stage 1 – Acid Stage:
   • Media: 0.1 N HCl (Simulated Gastric Fluid)
   • Volume: 750 mL
   • Duration: 2 hours
   • Acceptance: NMT 10% drug release
2. Stage 2 – Buffer Stage:
   • Media: pH 6.8 phosphate buffer
   • Volume: Adjust to 1000 mL by adding 250 mL of buffer
   • Duration: As per specification (e.g., NLT 80% in 45 minutes)

5.3 Sampling and Analysis

1. Withdraw 10 mL sample at specified time points (e.g., 5, 10, 15, 30, 45, 60 minutes).
2. Filter through 0.45 µm syringe filter.
3. Replace media volume after each withdrawal to maintain sink conditions.
4. Analyze using UV or HPLC at specific wavelength or retention time.

5.4 Method Validation

1. Specificity: No interference from media or excipients.
2. Linearity: r² ≥ 0.999 from 10% to 120% of target concentration.
3. Accuracy: 95%–105% recovery in all stages.
4. Precision: %RSD ≤ 2.0% for each time point.
5. Robustness: Evaluate agitation speed ±5 rpm, volume ±5%, and media pH ±0.1.

5.5 Acceptance Criteria

• No more than 10% of drug should dissolve in the acid stage.
• NLT 80% drug should dissolve in buffer stage within specified time (typically 45 minutes).

6. Abbreviations

• USP: United States Pharmacopeia
• HCl: Hydrochloric Acid
• NLT: Not Less Than
• NMT: Not More Than
• RSD: Relative Standard Deviation

7. Documents

1. Dissolution Run Log – Annexure-1
2. Dissolution Profile Data – Annexure-2
3. Validation Summary Report – Annexure-3

8. References

• USP <711>: Dissolution
• ICH Q2(R1): Validation of Analytical Procedures
• FDA Guidance: Dissolution Testing of Immediate Release Solid Oral Dosage Forms

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Devika Shah	Sanket Pawar	Sunita Reddy
Designation	Dissolution Scientist	QA Reviewer	Head – AMD
Department	Analytical Method Development	QA	Analytical Method Development

11. Annexures

Annexure-1: Dissolution Run Log

Run ID	Stage	Time	RPM	Media	Temp (°C)	Analyst
DRT-285-01	Buffer	45 min	75	pH 6.8 Buffer	37.0	Ajay Verma

Annexure-2: Dissolution Profile Data

Time (min)	% Drug Release
5	12%
15	45%
30	78%
45	85%

Annexure-3: Validation Summary Report

The two-stage dissolution method for enteric-coated delayed release tablets was validated as per ICH Q2(R1). Method demonstrated high specificity, accuracy, and reproducibility across both acid and buffer stages. Approved for use in QC and stability programs.

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
21/05/2025	2.0	Enhanced media transition strategy and validation robustness section	Annual Review	Sunita Reddy
15/08/2022	1.0	Initial SOP Release	New SOP	QA Head