surfaces after cleaning operations.

2. Scope

This SOP applies to all rinse sampling method development and validation activities performed by the Analytical Method Development (AMD) department for cleaning validation programs of equipment used in the production of APIs and formulations.

3. Responsibilities

• Analytical Scientist: Designs rinse sampling procedures and conducts recovery validation and detection limit assessment.
• QC Analyst: Performs replicate testing and supports in ruggedness and precision studies.
• QA Executive: Reviews and approves the rinse sampling method validation protocol and final report.

4. Accountability

The Head of Analytical Method Development is accountable for the development, validation, and implementation of scientifically justified and GMP-compliant rinse sampling methods.

5. Procedure

5.1 Selection of Rinse Solvent

1. Select solvent based on solubility of target analyte and material compatibility (e.g., WFI, acetonitrile, dilute NaOH).
2. Use highest grade solvents to minimize background contamination.

5.2 Preparation of Spiked Surfaces

1. Spike known amount of analyte onto representative surfaces (e.g., SS-316, glass, PTFE).
2. Allow to dry completely under controlled conditions before rinsing.

5.3 Rinse Sampling Procedure

1. Rinse surface with a fixed volume of solvent (e.g., 100 mL per 1000 cm²).
2. Collect rinse into sterile or clean collection container.
3. Agitate and transfer to appropriate container for analysis.

5.4 Analytical Method Selection

1. Use HPLC, TOC, UV spectrophotometry, or conductivity based on analyte type.
2. Use validated methods for quantification and sensitivity.

5.5 Recovery Study and Validation

1. Calculate percent recovery using:
   
   % Recovery = (Amount Recovered / Amount Spiked) × 100
2. Acceptable recovery:
   • ≥80% for API and cleaning agents
   • ≥50% for microbial rinses
3. Perform replicate testing (n=3) to assess repeatability and precision.

5.6 Documentation

1. Record all details including spiking concentration, rinse volume, surface area, analysis results, and calculations in Annexures.
2. Prepare a rinse method validation report and submit to QA.

6. Abbreviations

• SOP: Standard Operating Procedure
• TOC: Total Organic Carbon
• HPLC: High Performance Liquid Chromatography
• API: Active Pharmaceutical Ingredient
• QA: Quality Assurance

7. Documents

1. Rinse Sampling Recovery Log – Annexure-1
2. Rinse Volume and Surface Mapping Record – Annexure-2
3. Rinse Sampling Method Validation Report – Annexure-3

8. References

• FDA Guidance for Industry: Cleaning Validation
• ICH Q7: GMP for Active Pharmaceutical Ingredients
• WHO TRS 1019 Annex 3: Points to Consider in Cleaning Validation

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Kavita Joshi	Manoj Desai	Sunita Reddy
Designation	Analytical Scientist	QA Reviewer	Head – AMD
Department	Analytical Method Development	QA	Analytical Method Development

11. Annexures

Annexure-1: Rinse Sampling Recovery Log

Analyte	Surface	Spiked Amount (µg)	Recovered (µg)	Recovery (%)	Status
Ibuprofen	SS-316	100	88	88%	Pass

Annexure-2: Rinse Volume and Surface Mapping

Equipment	Surface Area (cm²)	Rinse Volume (mL)	Rinse Solvent
Fluid Bed Dryer	2500	250	WFI

Annexure-3: Rinse Sampling Method Validation Report

Rinse sampling method validated for Ibuprofen using WFI as rinse solvent. Method shows recovery of 88% with RSD of 5.1%. All validation parameters within acceptable range. Method approved for routine cleaning validation studies.

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
21/05/2025	2.0	Included microbial rinse validation option and updated annexures	Annual SOP Review	Sunita Reddy
08/05/2022	1.0	Initial SOP Release	New SOP	QA Head