ensure scientific justification, method reproducibility, and discriminatory power.

2. Scope

This SOP applies to all pharmaceutical products undergoing dissolution method development within the Analytical Method Development (AMD) laboratory, including immediate-release, modified-release, and novel oral dosage forms.

3. Responsibilities

• Analytical Scientist: Conducts apparatus screening trials and evaluates performance characteristics.
• Formulation Scientist: Provides formulation details influencing apparatus selection.
• Reviewer: Assesses suitability, scientific rationale, and compliance with compendial requirements.
• Head – AMD: Reviews and approves final selection and its documentation.

4. Accountability

The Head of Analytical Method Development is accountable for approving the selection of dissolution apparatus and ensuring it supports reliable, discriminatory, and reproducible testing of drug release profiles.

5. Procedure

5.1 Review of Dosage Form Characteristics

1. Gather critical data:
   • Dosage form type: tablet, capsule, suspension, etc.
   • Drug release mechanism: immediate, delayed, extended release
   • Formulation factors: disintegration time, buoyancy, gelling behavior
2. Record in Annexure-1: Dosage Form Assessment Log.

5.2 Understanding USP Apparatus Types

1. Apparatus I (Basket): For capsules and floating tablets.
2. Apparatus II (Paddle): For non-floating tablets and conventional forms.
3. Apparatus III (Reciprocating Cylinder): For modified release, especially bead-filled capsules.
4. Apparatus IV (Flow-Through Cell): For poorly soluble drugs and specialized release forms.
5. Apparatus V to VII: Advanced use, such as transdermal patches and chewable forms.

5.3 Selection Based on Preliminary Trials

1. Conduct trials using Apparatus I and II:
   • Use standard media (e.g., 900 mL, 0.1N HCl or pH 6.8 buffer)
   • Set paddle or basket at 50–100 rpm depending on label claim
2. Evaluate:
   • Disintegration or rupture
   • Tablet coning or sticking
   • Floating or gelling behavior
3. If performance is unsuitable, consider alternate apparatus (e.g., Apparatus III or IV).
4. Record all observations in Annexure-2: Apparatus Trial Record.

5.4 Discrimination and Reproducibility Testing

1. Use the selected apparatus to run trials on:
   • Innovator/reference product
   • Formulations with known variation in hardness, API particle size, or excipient ratios
2. Apparatus should provide discrimination between formulations.
3. Also check %RSD for 6 units: should be ≤ 10% at all time points.
4. Document in Annexure-3: Apparatus Suitability Summary.

5.5 Finalization and Justification

1. Select apparatus providing:
   • Reproducible release profile
   • Acceptable RSD
   • Discriminatory power
2. Document rationale for selection or deviation from pharmacopeial apparatus in Annexure-4: Justification Report.
3. Submit report for QA review and Head – AMD approval.

6. Abbreviations

• USP: United States Pharmacopeia
• RSD: Relative Standard Deviation
• IR: Immediate Release
• ER: Extended Release
• AMD: Analytical Method Development
• SOP: Standard Operating Procedure

7. Documents

1. Dosage Form Assessment Log – Annexure-1
2. Apparatus Trial Record – Annexure-2
3. Apparatus Suitability Summary – Annexure-3
4. Justification Report – Annexure-4

8. References

• USP <711> – Dissolution
• FDA Dissolution Methods Database
• ICH Q6A – Specifications
• FDA Guidance for Industry: Dissolution Testing

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Dosage Form Assessment Log

Formulation	Dose Form	Coating	Release Type	Additional Notes
Test Form A	Tablet	Film Coated	Immediate	Non-floating

Annexure-2: Apparatus Trial Record

Apparatus	RPM	Media	Volume	Behavior	Comment
Apparatus II	50	0.1N HCl	900 mL	Tablet coning	Not preferred
Apparatus I	100	0.1N HCl	900 mL	Uniform dispersion	Preferred

Annexure-3: Apparatus Suitability Summary

Apparatus	Formulation A	Formulation B	Discrimination	RSD (%)
Apparatus I	88%	71%	Yes	3.5%

Annexure-4: Justification Report

Apparatus I was selected based on better sample dispersion, discriminatory power between formulations, and acceptable precision. Apparatus II resulted in coning and poor reproducibility.

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
04/05/2025	2.0	Updated annexures, added discrimination study protocol	Annual SOP Review