conditions to address buoyancy, retention, and hydration behavior during drug release studies.

2. Scope

This SOP applies to all floating tablets, gastro-retentive systems, and swellable dosage forms evaluated in the Analytical Method Development (AMD) department for dissolution profiling and regulatory method development.

3. Responsibilities

• Analytical Scientist: Conducts method trials using suitable apparatus modifications and records dissolution data.
• Formulation Scientist: Provides information about dosage form design (e.g., polymers, swelling kinetics, buoyancy enhancers).
• Group Leader: Reviews method performance and recommends optimization steps.
• QA Executive: Ensures regulatory compliance of the selected method.

4. Accountability

The Head of Analytical Method Development is accountable for the scientific and regulatory integrity of the finalized dissolution method for these specialized dosage forms.

5. Procedure

5.1 Evaluation of Dosage Form Behavior

1. Identify formulation characteristics:
   • Floating time (initial and total)
   • Swelling index
   • Polymer hydration time
2. Perform visual studies in water or simulated gastric fluid to assess in situ behavior.

5.2 Apparatus Selection and Configuration

1. Use USP Apparatus I (Basket) when dosage form tends to float excessively and cannot be anchored.
2. Use USP Apparatus II (Paddle) with:
   • Sinkers (e.g., coil or helical wire sinkers) if the form needs partial retention
   • Custom mesh devices or magnets if required to maintain position in the media

5.3 Media and RPM Optimization

1. Select dissolution media to mimic gastric retention environment:
   • 0.1N HCl (pH 1.2) as default
   • Simulated gastric fluid (SGF) for biorelevant studies
2. Set RPM between 50–75 depending on formulation stability and media agitation effect.

5.4 Sampling Strategy

1. Ensure sample point is not blocked by floating dosage forms.
2. Use cannula with filter tip angled downward.
3. Sample at multiple time points (e.g., 1, 2, 4, 6, 8, 12 hr for extended release formats).

5.5 Method Optimization and Discrimination

1. Compare dissolution results from:
   • Different apparatus (Basket vs Paddle)
   • Sinker vs no sinker trials
   • Formulation/process variants
2. Use similarity factor (f2), RSD, and mean % release data to finalize discriminatory conditions.

5.6 Documentation

1. Record all observations and data in Annexure-1.
2. Summarize apparatus configuration and rationale in Annexure-2.
3. Include overlay plots and f2 calculations in Annexure-3.

6. Abbreviations

• SOP: Standard Operating Procedure
• SGF: Simulated Gastric Fluid
• RSD: Relative Standard Deviation
• f2: Similarity Factor
• RPM: Revolutions Per Minute

7. Documents

1. Buoyancy and Swelling Observation Log – Annexure-1
2. Apparatus Configuration and Justification Sheet – Annexure-2
3. Dissolution Profile Overlay and f2 Summary – Annexure-3

8. References

• USP <711> – Dissolution
• USP <1092> – The Dissolution Procedure: Development and Validation
• FDA Guidance: Extended Release Oral Dosage Forms

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Tanvi Joshi	Ramesh Bhatt	Sunita Reddy
Designation	Research Associate	QA Reviewer	Head – AMD
Department	Analytical Method Development	QA	Analytical Method Development

11. Annexures

Annexure-1: Buoyancy and Swelling Observation Log

Unit No.	Time (min)	Floating/Swelling Status	Observation
1	30	Floating	Form remained buoyant and began surface erosion

Annexure-2: Apparatus Configuration and Justification

USP Apparatus II with stainless steel sinker coil used to prevent buoyancy interference. 0.1N HCl selected based on gastric targeting. RPM finalized at 75.

Annexure-3: Dissolution Profile and f2 Comparison

Overlay graphs archived in digital path: AMD/FLOAT/220/2025. f2 values ranged from 41–53 across batch variants, confirming discriminative method.

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
21/05/2025	2.0	Expanded to include swelling and floating dual-behavior handling	Annual Review	Sunita Reddy
19/05/2022	1.0	Initial Release	New SOP	QA Head