to determine suitable storage durations and conditions, in compliance with GMP and ICH Q2(R1) requirements.

2. Scope

This SOP applies to all solution stability studies conducted for APIs and finished products during method development and validation activities within the Analytical Method Development department.

3. Responsibilities

• Analyst: Prepares solutions and conducts testing at predefined intervals.
• Group Leader: Reviews chromatograms and interprets results.
• QA Executive: Reviews data and verifies compliance with acceptance criteria.
• Department Head: Approves the final stability report and ensures compliance.

4. Accountability

The Department Head of Analytical Method Development is accountable for ensuring that all solution stability studies are performed, reviewed, and documented accurately.

5. Procedure

5.1 Selection of Samples

1. Identify critical solutions for which stability is to be evaluated:
   • Sample solutions
   • Standard solutions
   • Mobile phase (when used over extended periods)
   • Diluents (if pre-prepared or stored)

5.2 Preparation of Solutions

1. Prepare fresh solutions of standards and samples as per the analytical method.
2. Label solutions with:
   • Preparation date and time
   • Analyst initials
   • Storage condition

5.3 Storage Conditions

1. Store the solutions at pre-defined conditions based on product characteristics:
   • Room Temperature (25 ± 2°C)
   • Refrigerator (2–8°C)
   • Autosampler condition (ambient or cooled chamber)

5.4 Testing Intervals

1. Conduct analysis at the following intervals:
   • 0 hours (initial)
   • 2 hours
   • 4 hours
   • 8 hours
   • 24 hours
   • 48 hours
   • 72 hours
2. For longer-term stability (if needed), extend testing up to 7 days or 14 days.

5.5 Acceptance Criteria

1. Peak area or assay result must remain within ±2% of the initial reading.
2. There must be no new unknown peaks, degradation products, or shifts in retention time.
3. System suitability must be revalidated at each interval.

5.6 Documentation and Reporting

1. Record all data in Annexure-1: Solution Stability Data Log.
2. Include representative chromatograms from each interval in Annexure-2.
3. Summarize findings in Annexure-3: Solution Stability Summary Report.
4. QA must review and sign-off the final report.

6. Abbreviations

• SOP: Standard Operating Procedure
• API: Active Pharmaceutical Ingredient
• QA: Quality Assurance
• ICH: International Council for Harmonisation
• HPLC: High Performance Liquid Chromatography

7. Documents

1. Solution Stability Data Log – Annexure-1
2. Chromatogram Archive – Annexure-2
3. Stability Summary Report – Annexure-3

8. References

• ICH Q2(R1) – Validation of Analytical Procedures
• WHO Technical Report Series 996
• FDA Guidance for Industry – Stability Testing

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Vikram Naik	Reena D’Souza	Sunita Reddy
Designation	Sr. Analyst	QA Executive	Head – AMD
Department	Analytical Method Development	QA	Analytical Method Development

11. Annexures

Annexure-1: Solution Stability Data Log

Time (hrs)	Peak Area	% Change	RT (min)	Observation
0	245,600	—	5.1	Initial
4	243,200	-0.98	5.1	Stable
24	240,800	-1.96	5.2	Stable

Annexure-2: Chromatogram Archive

Chromatograms for each time point (0, 4, 8, 24, 48, 72 hours) attached in QA logbook ref: QA/AMD/CHROM/203/2025

Annexure-3: Solution Stability Summary Report

Solution Type	Storage Condition	Stability Duration	Conclusion
Standard Solution	25°C	48 hours	Stable
Sample Solution	2–8°C	72 hours	Stable

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
21/05/2025	2.0	Expanded procedure and Annexures	Annual Review	Sunita Reddy
11/02/2022	1.0	Initial Release	New SOP	QA Head